424B5 1 424b5_sabs_fy26_prosupp.htm 424B5 424B5

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-292482

The information in this prospectus supplement is not complete and may be changed. The Registrant may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus supplement is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where an offer or sale is not permitted.

Subject to completion, dated March 17, 2026

Preliminary Prospectus Supplement

(To Prospectus Dated January 7, 2026)

Shares of Common Stock

Pre-funded Warrants to Purchase up to Shares of Common Stock

Shares of Common Stock Underlying the Pre-funded Warrants

We are offering shares of our common stock, par value $0.0001 per share (“common stock”), and, in lieu of shares of common stock to investors that so choose, pre-funded warrants to purchase up to shares of our common stock (the “pre-funded warrants”) (and the shares of common stock issuable from time to time upon exercise of the pre-funded warrants), pursuant to this prospectus supplement and the accompanying prospectus. The pre-funded warrants will be exercisable immediately and are exercisable for one share of our common stock. The purchase price of each pre-funded warrant is equal to the purchase price at which a share of our common stock is sold in this offering, minus $0.0001, and the exercise price of each pre-funded warrant is $0.0001 per share of our common stock.

Our common stock is listed on The Nasdaq Capital Market under the symbol “SABS”. On March 16, 2026, the last reported sale price for our common stock on The Nasdaq Capital Market was $3.94 per share. There is no established public trading market for the pre-funded warrants, and we do not expect a market to develop. In addition, we do not intend to apply for listing of the pre-funded warrants on any securities exchange or recognized trading system.

We are an “emerging growth company” as defined in Section 2(a) of the Securities Act of 1933, as amended (the “Securities Act”), and a “smaller reporting company” as defined under Rule 405 of the Securities Act, and as such, we have elected to comply with certain reduced public company reporting requirements. See “Prospectus Supplement Summary— Implications of Being an Emerging Growth Company and a Smaller Reporting Company” on page S-1 of this prospectus.


	Per Share	Pre Pre-Funded Warrant	Total
Public offering price	$	$	$
Underwriting discounts and commissions(1)	$	$	$
Proceeds to us before expenses	$	$	$

(1)

See “Underwriting” for a description of the compensation payable to the underwriters.

We have granted the underwriters an option for a period of 30 days to purchase an additional shares of our common stock from us, at the public offering price, less the underwriting discounts and commissions. If the underwriters exercise the option in full, the total underwriting discounts and commissions payable by us will be

$ million, and the total proceeds to us, before expenses, will be $ million.

Investing in our securities involves a high degree of risk. Please read the section titled “Risk Factors” beginning on page S-9 of this prospectus supplement, page 7 of the accompanying prospectus, and in the documents incorporated by reference into this prospectus supplement and the accompanying prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved of anyone's investment in these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

Delivery of the shares of common stock and pre-funded warrants is expected to be made on or about March , 2026

Joint Bookrunning Managers

Jefferies UBS Investment Bank Citigroup Barclays

Lead Manager

Chardan

The date of this prospectus supplement is March , 2026

TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT


ABOUT THIS PROSPECTUS SUPPLEMENT	1
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	2
PROSPECTUS SUPPLEMENT SUMMARY	4
THE OFFERING	7
RISK FACTORS	9
USE OF PROCEEDS	12
DIVIDEND POLICY	12
DILUTION	13
MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES FOR NON-U.S. HOLDERS OF OUR SECURITIES	15
DESCRIPTION OF PRE-FUNDED WARRANTS	20
UNDERWRITING	22
LEGAL MATTERS	30
EXPERTS	30
WHERE YOU CAN FIND MORE INFORMATION	30
INFORMATION INCORPORATED BY REFERENCE	30

PROSPECTUS DATED JANUARY 7, 2026


		Page
ABOUT THIS PROSPECTUS		1
TRADEMARKS		1
PROSPECTUS SUMMARY		2
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS		4
RISK FACTORS		6
USE OF PROCEEDS		7
DESCRIPTION OF CAPITAL STOCK WE MAY OFFER		8
DESCRIPTION OF DEBT SECURITIES WE MAY OFFER		12
DESCRIPTION OF WARRANTS WE MAY OFFER		19
DESCRIPTION OF RIGHTS WE MAY OFFER		21
DESCRIPTION OF UNITS WE MAY OFFER		22
PLAN OF DISTRIBUTION		24
EXPERTS		25
LEGAL MATTERS		25
WHERE YOU CAN FIND MORE INFORMATION		25
INFORMATION INCORPORATED BY REFERENCE		27

ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement and the accompanying base prospectus are part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) utilizing a “shelf” registration process. The first part is this prospectus supplement, which describes the specific terms of this offering of common stock and pre-funded warrants and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus.

This prospectus supplement is not complete without, and may not be utilized except in connection with, the accompanying base prospectus and any amendments to such prospectus. This prospectus supplement provides you with specific information regarding the terms of this offering and our common stock, and also adds to and updates information contained in the accompanying base prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying base prospectus. The accompanying base prospectus provides more general information, some of which does not apply to this offering of our common stock.

Before buying any of the securities that we are offering hereby, we urge you to carefully read this prospectus supplement and all of the information incorporated by reference herein, as well as the additional information described under the headings “Where You Can Find More Information” and “Information Incorporated by Reference.” These documents contain important information that you should consider when making your investment decision.

To the extent there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in any document incorporated by reference in this prospectus supplement that was filed with the SEC before the date of this prospectus supplement, on the other hand, you should rely on the information in this prospectus supplement. If any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference in this prospectus supplement—the statement in the document having the later date modifies or supersedes the earlier statement.

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreement, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

We have not, and the underwriters have not, authorized anyone to provide you with any information other than that contained or incorporated by reference in this prospectus supplement and in the accompanying base prospectus or in any related free writing prospectus that we authorize for use in connection with this offering and to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. You should assume that the information appearing in this prospectus supplement, the documents incorporated by reference and the accompanying base prospectus or free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.

This prospectus supplement does not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in this prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful.

In this prospectus supplement, unless the context suggests otherwise, references to “SAB Biotherapeutics,” “SAB,” the “Company,” “we,” “us” and “our” refer to SAB Biotherapeutics, Inc.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and certain information incorporated herein by reference contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those discussed in the forward-looking statements. The statements contained in this prospectus that are not purely historical are forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Forward-looking statements are often identified by the use of words such as, but not limited to, “anticipate,” “believe,” “can,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “project,” “seek,” “should,” “strategy,” “target,” “will,” “would” and similar expressions or variations intended to identify forward-looking statements. These statements are based on the beliefs and assumptions of our management based on information currently available to management. Such forward-looking statements are subject to risks, uncertainties and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements.

These forward-looking statements include, among other things, statements about:

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the success, cost and timing of our product development activities and clinical trials, including statements regarding our plans for clinical development of our product candidates, the initiation and completion of clinical trials and related preparatory work and the expected timing of the availability of results of clinical trials;

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our ability to recruit and enroll suitable patients in our clinical trials;

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the potential indications, attributes and benefits of our product candidates;

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our ability to obtain and maintain regulatory approval for our product candidates, and any related restrictions, limitations or warnings in the label of an approved product candidate;

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our ability to obtain funding for our operations, including funding necessary to complete further development, approval and, if approved, commercialization of our product candidates;

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the period over which we anticipate our existing cash and cash equivalents will be sufficient to fund our operating expense and capital expenditure requirements;

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the potential for our business development efforts to maximize the potential value of our portfolio;

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our ability to identify, in-license or acquire additional product candidates;

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our ability to compete with other companies currently marketing or engaged in the development of treatments for the indications that we are pursuing for our product candidates;

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our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates and the duration of such protection;

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our ability to contract with and rely on third parties to assist in conducting our clinical trials and manufacturing our product candidates;

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our manufacturing capabilities, third-party contractor capabilities and strategy;

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our plans related to manufacturing, supply and other collaborative agreements;

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the size and growth potential of the markets for our product candidates, and our ability to serve those markets, either alone or in partnership with others;

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the rate and degree of market acceptance of our product candidates, if approved;

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the pricing and reimbursement of our product candidates, if approved;

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regulatory developments in the United States and foreign countries;

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the impact of laws, regulations, accounting standards, regulatory requirements, judicial decisions and guidance issued by authoritative bodies;

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our ability to attract and retain key scientific, medical, commercial or management personnel;

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our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

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our financial performance;

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our ability to maintain our listing on The Nasdaq Capital Market; and

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our ability to continue as a going concern.

Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by any such forward-looking statements, including those described in “Risk Factors” and elsewhere in this prospectus supplement, the accompanying prospectus, and in the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, forward-looking statements represent our management's beliefs and assumptions only as of the date of this prospectus supplement. You should read this prospectus supplement and the accompanying prospectus, and the documents incorporated by reference herein and therein, and with the understanding that our actual future results may be materially different from what we expect.

Moreover, neither we nor any other person assumes responsibility for the accuracy and completeness of these statements. Except as required by law, we assume no obligation to update these forward-looking statements publicly and actual results could differ materially from those anticipated in these forward-looking statements, even if new information becomes available in the future.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information contained elsewhere in, or incorporated by reference into, this prospectus supplement and the accompanying prospectus. Because it is only a summary, it does not contain all of the information that you should consider before investing in our common stock and it is qualified in its entirety by, and should be read in conjunction with, the more detailed information appearing elsewhere in this prospectus supplement, the accompanying prospectus, any free writing prospectus that we have authorized for use in connection with this offering and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. You should read all such documents carefully and you should pay special attention to the information contained under the caption entitled “Risk Factors” in this prospectus supplement, in our Quarterly Reports on Form 10-Q and Annual Reports on Form 10-K and in our other reports filed from time to time with the SEC, which are incorporated by reference into this prospectus supplement and the accompanying prospectus, before deciding to buy shares of our common stock.

Business Overview

We are a clinical-stage biopharmaceutical company focused on developing multi-specific, high-potency, human immunoglobulin G (“hIgG”) to treat and prevent immune and autoimmune disorders. Our programs are based on mechanisms of action that have achieved proof-of-concept in clinical trials in indications with significant unmet medical needs. We are focused on developing product candidates for disease targets where a differentiated approach has the greatest potential to be either first-in-class against novel targets or best-in-class against complex targets to treat diseases, including type 1 diabetes (“T1D”) and other autoimmune disorders. Our lead candidate, SAB-142, targets autoimmune T1D with a disease-modifying therapeutic approach that aims to potentially change the T1D treatment paradigm by delaying onset and potentially preventing disease progression of Stage 3 T1D patients.

Using advanced genetic engineering and antibody science, we developed a proprietary technology which holds the potential to generate additional novel therapeutic candidates utilizing the human immune response, without the need for human donors or convalescent plasma. We believe it is the only technology capable of producing disease-targeted, hIgG in large quantities without human plasma donors.

We have optimized genetic engineering in the development of transchromosomic cattle, or Tc-Bovine™, to produce hIgG. Our engineering of our production platform drives IgG1 production across our pipeline. In addition, this differentiated approach using polyclonal antibodies has no biosimilar pathway, which provides a significant barrier to competitive polyclonal approaches.

Our proprietary platform holds the potential to generate additional novel therapeutic candidates to expand our pipeline, utilizing the human immune response to generate the optimal repertoire of hIgG for drug targets of interest. Our drug development production system is able to generate a diverse repertoire of specifically targeted, high-potency, hIgGs that can bind to multiple sites on targeted immunogens, making them ideally suited to address the complexities associated with many immune-mediated disorders and address a wide range of serious unmet needs in human diseases.

SAB-142: Our Lead Product Candidate

Our wholly owned lead product candidate, SAB-142 is a potentially disease-modifying, redosable immunotherapy in clinical development for the treatment of autoimmune T1D. SAB-142 is a multi-specific, fully human anti-thymocyte globulin with a mechanism of action analogous to that of rabbit anti-thymocyte globulin (“rATG”). rATG has demonstrated in multiple clinical trials the ability to slow disease progression in patients with new- or recent-onset of Stage 3 T1D. SAB-142, like rATG, directly targets multiple immune cells involved in destroying pancreatic beta cells, including modulation of “bad acting” T-lymphocytes. By stopping immune cells from attacking beta cells, this treatment has the potential to preserve insulin-producing beta cells. The mechanism of action of SAB-142 has been clinically validated in numerous clinical trials with a rATG. In addition, data from approximately 800 human subjects have been treated with antibodies produced by our platform, including in the Phase 1 study of SAB-142, where we have seen no incidence of serum sickness and neutralizing anti-drug antibodies. We expect this finding to continue through the clinical development of SAB-142.

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There is an established regulatory path for T1D indications using the SAB-142 modality. Our regulatory pathway has also been established with the United States Food and Drug Administration (“FDA”), the United Kingdom Medicines and Healthcare products Regulatory Agency, and the Therapeutic Good Administration in Australia. The FDA regulates polyclonal hIgG and mAbs differently, as mAbs are regulated through the Center for Drug Evaluation and Research while pAbs are regulated by the Center for Biologics Evaluation and Research (“CBER”). CBER has approved more than 30 immunoglobulin products from both human- and animal-derived plasma. Further, CBER is very familiar with our production platform and pAb products. We have navigated three SAB drug products through seven clinical trials with one product having advanced to Phase 3, building our safety database as well as positive efficacy data. As our lead program SAB-142 advances, we intend to expand our pipeline in complementary indications through strategic utilization of our platform.

We received an Investigational New Drug clearance from the FDA in May 2024 and announced positive topline data from our Phase 1 clinical trial of SAB-142 in January 2025, December 2025, and March 2026. We are advancing SAB-142 into a Phase 2b clinical trial called the SAFEGUARD study. On May 29, 2025, we held a constructive Type B meeting with the FDA. The meeting followed positive topline data from a Phase 1 single-ascending dose trial in healthy volunteers for SAB-142. The primary discussion centered on questions related to all aspects of SAB-142’s Phase 2b SAFEGUARD clinical trial design and chemistry, manufacturing, and controls processes. The FDA provided clear, constructive, and actionable guidance during the discussion leading to alignment on the design and advancement of our Phase 2b SAFEGUARD study. We confirmed our intent with the FDA to utilize the data from this study as supportive evidence for future regulatory approval.

Recent Events – Additional Phase 1 Data for SAB-142

On March 10, 2026, we announced additional data from our Phase 1 HUman anti-thymocyte biologic in first-in-MAN (HUMAN) clinical trial of SAB-142. In the trial, the established T1D adult patient cohort demonstrated early signals of C-peptide preservation aligned with the anticipated mechanism of action of SAB-142. In the T1D cohort (n=6), SAB-142 treated study participants (n=4) showed no decrease in C-peptide levels at Day 120 compared to baseline. The placebo study participant showed a decrease in C-peptide compared to the baseline. The Phase 1 T1D cohort included six adult participants (n=6), with four receiving SAB-142 at 2.5 mg/kg (n=4) and two receiving placebo (n=2). Participants ranged in age from 19 to 40 years. All established T1D patients (Stage 3 T1D diagnosis within 28-40 months at the time of randomization) had residual beta function (C-peptide >0.2 nmol/L) and at least one T1D autoantibody at baseline. Phase 1 study efficacy endpoints were measured at the End of Study Day 120 post SAB-142 administration. One placebo participant (n=1) completed through Day 120 as the other placebo participant discontinued early due to personal reasons. Participants treated with SAB-142 (2.5 mg/kg) demonstrated preservation in C-peptide levels compared to baseline with mean values increasing above baseline by Day 120. In contrast, the placebo treated participant showed a decline in C-peptide consistent with the predicted rate of disease progression. For reference, the TN19 Placebo Cohort 1 is modeled using a historical C-peptide trajectory based on historical placebo arm from the TN19 study. By Day 120, SAB-142 shows divergence from both the study placebo arm and the TN19 modeled placebo cohort, supporting a pharmacodynamic effect consistent with the preservation of beta cell function in adult patients with established T1D.

Corporate Information

We were incorporated in the State of Delaware on November 12, 2020, as a special purpose acquisition company under the name Big Cypress Acquisition Corp. (“BCYP”). On January 14, 2021, BCYP completed its initial public offering. On October 22, 2021, BCYP consummated a business combination with SAB Biotherapeutics, Inc. (the “Business Combination”), which changed its name to SAB Sciences, Inc. In connection with the closing of the business combination, BCYP changed its name to SAB Biotherapeutics, Inc. and SAB Sciences, Inc. became a subsidiary of SAB Biotherapeutics, Inc.

Our principal executive offices are located at 777 W 41st St., Suite 401 Miami Beach, Florida 33140, and our telephone number is (305)-845-2813. Our website is located at https://www.sab.bio. We do not incorporate by reference into this prospectus the information on, or accessible through, our website. Our common stock trades on The Nasdaq Capital Market under the symbol “SABS”.

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Implications of Being an Emerging Growth Company and a Smaller Reporting Company

We are an “emerging growth company,” as defined in Section 2(a) of the Securities Act, and therefore we intend to take advantage of certain exemptions from various public company reporting requirements, including not being required to have our internal control over financial reporting audited by our independent registered public accounting firm pursuant to Section 404(b) of the Sarbanes-Oxley Act of 2002, reduced disclosure obligations regarding executive compensation in this prospectus, our periodic reports and our proxy statements and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and any golden parachute payments not previously approved. We will remain an emerging growth company until the earliest of (i) the last day of the fiscal year in which the market value of our common stock that is held by non-affiliates equals or exceeds $700 million as of the end of that year’s second fiscal quarter, (ii) the last day of the fiscal year in which we have total annual gross revenue of $1.235 billion or more during such fiscal year (as indexed for inflation), (iii) the date on which we have issued more than $1 billion in non-convertible debt in the prior three-year period or (iv) December 31, 2026.

We are also a “smaller reporting company” as defined under the Securities Act and the Exchange Act. We may continue to be a smaller reporting company so long as either (i) the market value of shares of our common stock held by non-affiliates is less than $250 million or (ii) our annual revenue was less than $100 million during the most recently completed fiscal year and the market value of shares of our common stock held by non-affiliates is less than $700 million. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and have reduced disclosure obligations regarding executive compensation, and, similar to emerging growth companies, if we are a smaller reporting company under the requirements of (ii) above, we would not be required to obtain an attestation report on internal control over financial reporting issued by our independent registered public accounting firm.

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THE OFFERING
Common stock offered	shares of our common stock (or shares if the underwriters exercise their option to purchase additional shares in full).
Pre-funded warrants offered by us	We are also offering, in lieu of shares of our common stock to investors that so choose, pre-funded warrants to purchase up to shares of our common stock. Each pre-funded warrant will have an initial exercise price per share of $0.0001, subject to certain adjustments. The purchase price of each pre-funded warrant is equal to the price at which the share of our common stock is being sold in this offering, minus $0.0001. The pre-funded warrants are exercisable immediately and may be exercised at any time until all of the pre-funded warrants are exercised in full. For more information, see the section titled “Description of Pre-Funded Warrants” on page S-20 of this prospectus supplement. This prospectus supplement also relates to the offering of the shares of our common stock issuable upon exercise of the pre-funded warrants.
Common stock outstanding before this offering	47,609,899 shares of common stock
Common stock to be outstanding after this offering	shares of common stock (or shares if the underwriters exercise their option to purchase additional shares in full), in each case assuming none of the pre-funded warrants issued in this offering are exercised.
Offering price per share of common stock	$ per share (or $ per pre-funded warrant).
Option to purchase additional shares	We have granted the underwriters an option to purchase up to an additional shares of our common stock from us, at the public offering price, less the underwriting discounts and commissions, for a period of 30 days after the date of this prospectus supplement.
Use of Proceeds	We estimate that our net proceeds from this offering will be approximately $ million, excluding the proceeds, if any, from the exercise of the pre-funded warrants and after deducting underwriting discounts and commissions and estimated offering expenses payable by us. We intend to use the net proceeds we receive from this offering, together with our existing cash, cash equivalents and marketable securities, primarily to fund the continued development of our clinical stage product candidate, SAB 142 through ongoing and planned clinical trials, as well as for related manufacturing, regulatory, and operational activities, and for working capital and general corporate purposes. See “Use of Proceeds” for additional information.
Risk Factors	Investing in our securities involves a high degree of risk and purchasers of our securities may lose their entire investment. See the section titled “Risk Factors” in this prospectus supplement and the accompanying prospectus for a discussion of factors you should carefully consider before deciding to invest in our securities.
The Nasdaq Capital Market Symbol	“SABS”. There is no established public trading market for the pre-funded warrants and we do not expect a market to develop. In

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	addition, we do not intend to apply for listing of the pre-funded warrants on any securities exchange or recognized trading system.
The number of shares of our common stock that will be outstanding immediately after this offering set forth above is based on 47,609,899 shares of our common stock outstanding as of December 31, 2025, and excludes the shares of common stock issuable upon exercise of the pre-funded warrants being offered by us in this offering. The number of shares outstanding as of December 31, 2025 as used throughout this prospectus supplement, unless otherwise indicated, excludes: • 2,233,407 shares issuable upon exercise of outstanding warrants with a weighted average exercise price of $36.84; • 20,887,772 shares issuable upon exercise of our issued and outstanding stock options with a weighted-average exercise price of $2.93 per share; • 14,639 shares issuable for restricted stock grants outstanding; • 11,706,457 shares reserved for issuance, but not subject to outstanding options or restricted stock awards, under our incentive equity plans; • 100,000 shares reserved for issuance under our employee stock purchase plan; • 4,504,824 shares issuable upon conversion of our Series A Preferred Stock, including shares of Series A Preferred Stock issuable upon exercise of Series A Preferred Stock purchase warrants; and • 213,855,800 shares issuable upon conversion of our Series B Preferred Stock, including shares of Series B Preferred Stock issuable upon exercise of Series B Preferred Stock purchase warrants.

Unless otherwise indicated, all information in this prospectus supplement assumes no exercise of the outstanding common stock purchase warrants or options to purchase our common stock and no vesting or settlement of restricted stock grants described above after December 31, 2025, no exercise by the underwriters of their option to purchase up to additional shares of our common stock in this offering and no exercise of the pre-funded warrants we are offering to certain investors.

Up to $75.0 million of shares of our common stock may be sold from time to time under the sales agreement (the “Sales Agreement”), dated December 29, 2025, for our “at-the-market” program (“ATM Program”) with UBS Securities LLC, as sales agent. As of the date of this prospectus supplement, no sales have been made under the ATM Program.

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RISK FACTORS

Investing in our securities involves a high degree of risk. Before making a decision to invest in our securities, in addition to carefully considering the other information contained in this prospectus supplement, in the accompanying base prospectus and incorporated by reference herein or therein, you should carefully consider the risks described under the caption “Risk Factors” contained in the accompanying base prospectus, and any related free writing prospectus, and the risks discussed under the caption “Risk Factors” contained in our most recent annual report on Form 10-K and in our most recent quarterly reports on Form 10-Q, as well as any amendments thereto, which are incorporated by reference into this prospectus supplement in their entirety, together with other information in this prospectus supplement, the documents incorporated by reference, and any free writing prospectus that we may authorize for use in connection with a specific offering. See “Where You Can Find More Information” and “Incorporation by Reference.”

Risks Related to this Offering

If you purchase securities in this offering, you may suffer immediate and substantial dilution of your investment.

The offering price per share (or pre-funded warrant) in this offering will exceed the net tangible book value per share of our common stock outstanding prior to this offering. Therefore, if you purchase securities in this offering, you will pay an offering price per share (or pre-funded warrant) that substantially exceeds our net tangible book value per share after this offering. To the extent shares are issued under outstanding options at exercise prices lower than the price of our common stock in this offering, you will incur further dilution. Our historical net tangible book value as of December 31, 2025 was approximately $151.49 million, or $3.18 per share. After giving effect to this offering at the offering price of $ per share, and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us (but excluding the shares of common stock to be issued and the proceeds received, if any, from exercises of the pre-funded warrants offered hereby), you will experience immediate dilution of $ per share, representing the difference between our as adjusted net tangible book value per share as of December 31, 2025 after giving effect to this offering (but without giving effect to the exercise of pre-funded warrants offered hereby) at the offering price. See the section entitled “Dilution” below for a more detailed illustration of the dilution you would incur if you participate in this offering.

We have broad discretion over the use of our existing cash, cash equivalents and marketable securities and the net proceeds from this offering and may not use them effectively.

Our management will have broad discretion over the application of our existing cash, cash equivalents and marketable securities and the net proceeds from this offering, including for any of the purposes described in the section titled “Use of Proceeds,” and you will not have the opportunity as part of your investment decision to assess whether such proceeds are being used appropriately. Because of the number and variability of factors that will determine our use of our existing cash and cash equivalents and the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. Our management might not apply our existing cash and cash equivalents and marketable securities and the net proceeds from this offering in ways that ultimately increase the value of your investment. The failure by our management to apply these funds effectively could harm our business. Pending the use of the net proceeds from this offering, we may invest such net proceeds in short-term, investment-grade, interest-bearing securities. These investments may not yield a favorable return to our stockholders. If we do not invest or apply the net proceeds from this offering in ways that enhance stockholder value, we may fail to achieve expected financial results, which could cause our stock price to decline.

You may experience future dilution as a result of future equity offerings.

In order to raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share (or pre-funded warrant) in this offering, including through our “at-the-market” equity offering program.

In December 2025, we entered into the Sales Agreement with UBS Securities LLC, pursuant to which we filed a registration statement on Form S-3 including a prospectus supplement under which we may sell and issue shares of our common stock having an aggregate offering price of up to $75.0 million from time to time in transactions that

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are deemed to be an “at-the-market offering” as defined in Rule 415(a)(4) under the Securities Act. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to those of existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering.

We may seek additional non-dilutive financing, however, we may be unable to secure such financing on favorable terms or at all, which could require us to seek dilutive financing. If adequate funds are not available on acceptable terms, we may be unable to fund our capital requirements.

Future sales or issuances of our common stock in the public markets, or the perception of such sales, could depress the trading price of our common stock.

The sale of a substantial number of shares of our common stock or other securities convertible into or exchangeable for our common stock in the public markets, or the perception that such sales could occur, could depress the market price of our common stock and impair our ability to raise capital through the sale of additional equity securities. We may sell large quantities of our common stock at any time pursuant to this prospectus supplement or in one or more separate offerings. We cannot predict the effect that future sales of common stock or other equity-related securities would have on the market price of our common stock.

There is no public market for the pre-funded warrants being offered by us in this offering.

There is no established public trading market for the pre-funded warrants being sold in this offering, and we do not expect a market to develop. In addition, we do not intend to apply to list the pre-funded warrants on any securities exchange or recognized trading system. Without an active market, the liquidity of the pre-funded warrants will be limited. We will not receive a significant amount or any additional funds upon the exercise of the pre-funded warrants.

Holders of the pre-funded warrants will have no rights as common stockholders until they acquire our common stock.

Until you acquire shares of our common stock upon exercise of the pre-funded warrants, you will have no rights with respect to our common stock issuable upon exercise of the pre-funded warrants, including the right to vote or respond to tender offers. Upon exercise of your pre-funded warrants, you will be entitled to exercise the rights of a common stockholder only as to matters for which the record date occurs after the exercise date.

We will not receive any meaningful amount of additional funds upon the exercise of the pre-funded warrants.

Each pre-funded warrant will be exercisable until it is fully exercised and by means of payment of the nominal cash purchase price upon exercise or by means of a “cashless exercise” according to a formula set forth in the pre-funded warrant. Accordingly, we will not receive any meaningful additional funds upon the exercise of the pre-funded warrants.

Significant holders or beneficial holders of our common stock may not be permitted to exercise certain of the pre-funded warrants that they hold.

A holder of a pre-funded warrant will not be entitled to exercise any portion of any pre-funded warrant, which, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by the holder (together with its affiliates) to exceed 4.99% or 9.99%, as the case may be, of the number of shares of our common stock outstanding immediately after giving effect to the exercise of the pre-funded warrant unless such percentage is increased upon at least 61 days’ prior notice, but not in excess of 19.99%. As a result, you may not be able to exercise your pre-funded warrants for shares of our common stock at a time when it would be financially beneficial for you to do so. In such circumstance, you could seek to sell your pre-funded warrants to realize value, but you may be unable to do so in the absence of an established trading market for the pre-funded warrants.

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If we do not maintain a current and effective registration statement relating to the shares of our common stock issuable upon exercise of the pre-funded warrants, holders will only be able to exercise such pre-funded warrants on a “cashless basis.”

If we do not maintain a current and effective registration statement relating to the shares of our common stock issuable upon exercise of the pre-funded warrants at the time that holders wish to exercise such pre-funded warrants, they will only be able to exercise them on a “cashless basis” provided that an exemption from registration is available. As a result, the number of shares of our common stock that holders will receive upon exercise of the pre-funded warrants will be fewer than it would have been had such holder exercised such pre-funded warrants for cash, and holders may be limited in their ability to immediately sell shares upon exercise subject to volume or other securities law limitations. Further, if an exemption from registration is not available, holders would not be able to exercise on a cashless basis and would only be able to exercise their pre-funded warrants for cash if a current and effective registration statement relating to the shares of our common stock issuable upon exercise of the pre-funded warrants is available.

We will require additional capital funding, the receipt of which may impair the value of our common stock.

Our future capital requirements depend on many factors, including our clinical trial, research, development, sales and marketing activities. We will need to raise additional capital through public or private equity or debt offerings or through arrangements with strategic partners or other sources in order to continue to develop our drug candidates. There can be no assurance that additional capital will be available when needed or on terms satisfactory to us, if at all. To the extent we raise additional capital by issuing equity securities, our stockholders may experience substantial dilution and the new equity securities may have greater rights, preferences or privileges than our existing common stock. Further, we have a significant number of stock options outstanding. The exercise of outstanding stock options may result in further dilution of your investment.

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USE OF PROCEEDS

We estimate that the net proceeds we will receive from this offering will be approximately $ million (or approximately $ million if the underwriters exercise their option to purchase additional shares in full), after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We intend to use the net proceeds from this offering, together with our existing cash, cash equivalents and marketable securities, to fund the continued development of our clinical stage product candidate, SAB 142 through ongoing and planned clinical trials, as well as for related manufacturing, regulatory, and operational activities, and for working capital and general corporate purposes..

Our expected use of the net proceeds to us from this offering represents our current intentions based upon our present plans and business condition. The amounts and timing of our actual expenditures will depend on numerous factors, including the progress of our research and development efforts, the status of and results from our current or future clinical trials, the timing of regulatory submissions and any unforeseen cash needs. Accordingly, our management will have broad discretion in the application of any net proceeds from this offering.

We believe that the anticipated net proceeds from this offering, together with our existing cash and cash equivalents, will enable us to fund our operating expenses and capital expenditure requirements through .

Until we use the net proceeds of this offering for the purposes described above, we intend to invest any funds we receive in short-term, investment-grade, interest-bearing instruments and U.S. government securities. We cannot predict whether these investments will yield a favorable return.

DIVIDEND POLICY

We have never declared or paid any cash dividends on our shares of common stock and do not anticipate paying any cash dividends in the foreseeable future. Payment of cash dividends, if any, in the future will be at the discretion of our board of directors and will depend on then-existing conditions, including our financial condition, operating results, contractual restrictions, capital requirements, business prospects and other factors our board of directors may deem relevant.

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DILUTION

If you invest in this offering, your ownership interest will be diluted immediately to the extent of the difference between the public offering price per share of common stock or pre-funded warrant in this offering and the as adjusted net tangible book value per share of our common stock after giving effect to this offering.

As of December 31, 2025, we had a historical net tangible book value of approximately $151.49 million, or approximately $3.18 per share of common stock, based on 47,609,899 shares of common stock outstanding. Our historical net tangible book value per share represents total tangible assets less total liabilities, divided by the number of shares of common stock outstanding.

After giving effect to the sale of (i) shares of our common stock in this offering at the offering price of $ per share and (ii) pre-funded warrants to purchase $ shares of our common stock in this offering at the offering price minus $0.0001 (excluding, in each case, the shares of common stock to be issued and the proceeds received, if any, from exercises of the pre-funded warrants), and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us, our as adjusted net tangible book value as of December 31, 2025 would have been approximately, $ million, or $ per share of our common stock. This represents an immediate increase in as adjusted net tangible book value of $ per share to our existing stockholders and an immediate dilution of $ per share to investors purchasing our securities in this offering. The following table illustrates this dilution on a per share basis:


Public offering price per share
Net tangible book value per share as of December 31, 2025	$	3.18
Increase in net tangible book value per share attributable to investors purchasing shares in this offering
As adjusted net tangible book value per share after giving effect to this offering
Dilution per share to investors in this offering

Assuming the pre-funded warrants were immediately and fully exercised, this would result in an as adjusted net tangible book value per share, after giving effect to this offering and warrant exercise, of $ million, or $ per share. This represents an increase in net tangible book value of $ per share to existing stockholders and dilution in net tangible book value per share of $ to new investors participating in this offering.

If the underwriters exercise their option to purchase up to additional shares in full at the public offering price of $ per share, and after deducting underwriting discounts and commissions and estimated offering expenses payable by us, the as-adjusted net tangible book value would be $ per share, representing an immediate increase in net tangible book value of $ per share to existing stockholders and an immediate dilution in as-adjusted net tangible book value of $ per share to new investors purchasing shares of our common stock in this offering.

The number of shares of our common stock to be outstanding after this offering set forth above is based on 47,609,899 shares of our common stock outstanding as of December 31, 2025, and excludes the shares of common stock issuable upon exercise of the pre-funded warrants being offered by us in this offering. The number of shares outstanding as of December 31, 2025, unless otherwise indicated, excludes:

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2,233,407 shares issuable upon exercise of outstanding common stock purchase warrants with a weighted average exercise price of $36.84;

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20,887,772 shares issuable upon exercise of our issued and outstanding stock options with a weighted-average exercise price of $2.93 per share;

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14,639 shares issuable for restricted stock grants outstanding;

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11,706,457 shares reserved for issuance, but not subject to outstanding options or restricted stock awards, under our incentive equity plans;

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100,000 shares reserved for issuance under our employee stock purchase plan;

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4,504,824 shares issuable upon conversion of our Series A Preferred Stock, including shares of Series A Preferred Stock issuable upon exercise of Series A Preferred Stock purchase warrants; and

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213,855,800 shares issuable upon conversion of our Series B Preferred Stock, including shares of Series B Preferred Stock issuable upon exercise of Series B Preferred Stock purchase warrants.

To the extent that outstanding options, common stock purchase warrants, shares of Series A Preferred Stock or Series B Preferred Stock outstanding as of December 31, 2025 or pre-funded warrants have been or may be exercised or other shares issued, investors purchasing our common stock in this offering may experience further dilution. In addition, we may choose to raise additional capital due to market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES

FOR NON-U.S. HOLDERS OF OUR SECURITIES

The following is a general discussion of material U.S. federal income tax considerations and certain U.S. federal estate tax considerations relating to the acquisition, ownership, and disposition of our securities applicable to non-U.S. holders that purchase our securities in this offering and hold it as a “capital asset” within the meaning of Section 1221 of the Code (generally, property held for investment). For purposes of this discussion, a “non-U.S. holder” means a beneficial owner of our securities (other than an entity or arrangement that is treated as a partnership for U.S. federal income tax purposes) that is not, for U.S. federal income tax purposes, any of the following:

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an individual who is a citizen or resident of the United States;

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a corporation (or entity treated as a corporation for United States federal income tax purposes) created or organized in or under the laws of the United States, any state thereof or the District of Columbia, or otherwise treated as a domestic corporation;

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an estate, the income of which is includable in gross income for U.S. federal income tax purposes regardless of its source; or

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a trust if (i) a court within the United States is able to exercise primary supervision over the administration of the trust and one or more “United States persons,” as defined under the U.S. Internal Revenue Code of 1986, as amended (the “Code”), (“U.S. persons”) have the authority to control all substantial decisions of the trust or (ii) such trust has made a valid election to be treated as a U.S. person for U.S. federal income tax purposes.

If a partnership (or other entity or arrangement treated as a partnership for U.S. federal income tax purposes) holds our securities, the tax treatment of a partner therein will generally depend on the status of the partner and the activities of the partnership. Partners of a partnership holding our securities should consult their tax advisors as to the particular U.S. federal income tax consequences applicable to them.

This discussion is based on current provisions of the Code, final, temporary and proposed Treasury regulations promulgated thereunder (the “Treasury Regulations”), judicial decisions, published rulings and administrative pronouncements of the U.S. Internal Revenue Service, or IRS, all in effect as of the date of this prospectus supplement and all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any change could alter the tax consequences to non-U.S. holders described herein. There can be no assurance that the IRS will not challenge one or more of the tax consequences described herein.

This discussion does not address all aspects of U.S. federal income and estate taxation that may be relevant to a particular non-U.S. holder in light of that non-U.S. holder’s particular circumstances nor does it address any aspects of U.S. state or local or non-U.S. taxes, other U.S. federal tax, the alternative minimum tax, or the tax on net investment income. This discussion also does not consider any specific facts or circumstances that may apply to a non-U.S. holder and does not address the special tax rules applicable to particular non-U.S. holders, such as:

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banks, insurance companies and other financial institutions;

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brokers or dealers or traders in securities;

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tax-exempt organizations;

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tax-qualified retirement plans;

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persons who hold or receive our common stock pursuant to the exercise of any employee stock option

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or otherwise as compensation;

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“qualified foreign pension funds” as defined in Section 897(l)(2) of the Code and entities all of the

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interests of which are held by qualified foreign pension funds;

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persons that own, or have owned, actually or constructively, more than 5% of our stock at any time;

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persons who hold our securities as part of a straddle, hedge, conversion transaction, synthetic security

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or other integrated investment or who have elected to mark securities to market;

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controlled foreign corporations, passive foreign investment companies, and corporations that accumulate

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earnings to avoid U.S. federal income tax;

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non-U.S. governments and governmental organizations; and

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former citizens or long-term residents of the United States.

THIS SUMMARY IS NOT INTENDED TO CONSTITUTE A COMPLETE DESCRIPTION OF ALL TAX CONSEQUENCES FOR NON-U.S. HOLDERS RELATING TO THE OWNERSHIP AND DISPOSITION OF OUR SECURITIES. PROSPECTIVE HOLDERS OF OUR SECURITIES SHOULD CONSULT WITH THEIR TAX ADVISORS REGARDING THE TAX CONSEQUENCES TO THEM (INCLUDING THE APPLICATION AND EFFECT OF ANY STATE, LOCAL, NON-U.S. INCOME AND OTHER TAX LAWS) OF THE ACQUISITION, OWNERSHIP AND DISPOSITION OF OUR SECURITIES.

Characterization of the Pre-Funded Warrants for Tax Purposes

Although the characterization of the pre-funded warrants for U.S. federal income tax purposes is not entirely clear, because the exercise price of the pre-funded warrants is a nominal amount, we intend to treat the pre-funded warrants as our common stock for U.S. federal income tax purposes and a holder of pre-funded warrants should generally expect to be taxed in the same manner as a holder of our common stock as described below. Accordingly, for U.S. federal income tax purposes, no gain or loss should be recognized upon the exercise of a pre-funded warrant (except to the extent of cash received in lieu of a fractional share), and upon exercise, the holding period of the share of common stock received should include the holding period of the pre-funded warrant. Similarly, the tax basis of a share of common stock received upon exercise of a pre-funded warrant should include the tax basis of the pre-funded warrant increased by the exercise price of $0.0001 per share. The balance of this discussion generally assumes that the characterization described above is respected for U.S. federal income tax purposes.

Our position with respect to the characterization of pre-funded warrants is not binding on the IRS and the IRS may treat the pre-funded warrants as warrants to acquire our common stock and, if so, the tax considerations to a holder with respect to an investment in our pre-funded warrants could differ from the description below. In addition, the United States federal income tax treatment of a cashless exercise of pre-funded warrants is unclear, and the tax consequences of a cashless exercise could differ from the consequences upon the exercise of a pre-funded warrant described in the preceding paragraph. Each holder should consult its tax advisor regarding the characterization of pre-funded warrants for U.S. federal income tax purposes, and the consequences of an investment in the pre-funded warrants based on such holder’s own particular facts and circumstances.

Distributions on Common Stock and Pre-Funded Warrants

As discussed under “Dividend Policy” above, we do not expect to make distributions on our common stock or pre-funded warrants in the foreseeable future. However, if we do make distributions of cash or property on our common stock or pre-funded warrants, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts of distributions not treated as dividends for U.S. federal income tax purposes will first constitute a tax-free return of capital of the non-U.S. holder’s investment and be applied against and reduce a non-U.S. holder’s adjusted tax basis in its common stock or pre-funded warrants, but not below zero. Any remaining excess will be treated as capital gain and will be treated as described below under “Gain on Sale or Other Disposition of Common Stock and Pre-Funded Warrants.” Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of the withholding rules discussed below we or the applicable withholding agent may treat the entire distribution as a dividend. Any such distributions will also be subject to the discussions below under the headings “FATCA” and “Backup Withholding, Information Reporting and Other Reporting Requirements.”

Subject to the discussion in the next two paragraphs, dividends paid to a non-U.S. holder generally will be subject to withholding of U.S. federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder’s country of residence.

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Dividends we pay to a non-U.S. holder that are effectively connected with such non-U.S. holder’s conduct of a trade or business within the United States (and, if required by an applicable tax treaty, are attributable to a U.S. permanent establishment or a fixed base maintained by such non-U.S. holder) will generally be exempt from the U.S. federal withholding tax described above, if the non-U.S. holder complies with applicable certification and disclosure requirements (generally including provision of a valid IRS Form W-8ECI (or applicable successor form) certifying that the dividends are effectively connected with the non-U.S. holder’s conduct of a trade or business within the United States). Instead, such dividends generally will be subject to U.S. federal income tax on a net income basis, at regular U.S. federal income tax rates as would apply if such holder were a U.S. person (as defined in the Code). Any U.S. effectively connected income received by a non-U.S. holder that is classified as a corporation for U.S. federal income tax purposes may also be subject to an additional “branch profits tax” at a rate of 30% (or such lower rate as may be specified by an applicable income tax treaty).

A non-U.S. holder of our common stock or pre-funded warrants who claims the benefit of an applicable income tax treaty between the United States and such holder’s country of residence generally will be required to provide a properly executed IRS Form W-8BEN or W-8BEN-E (or successor form) and satisfy applicable certification and other requirements. Non-U.S. holders are urged to consult their tax advisors regarding their entitlement to benefits under a relevant income tax treaty and the specific methods available to them to satisfy these requirements.

A non-U.S. holder of a pre-funded warrant is expected to receive any distributions paid with respect to common stock prior to the exercise of the pre-funded warrant and, in such case, would be taxed in the same manner as a non-U.S. holder of common stock that receives such a distribution. However, under certain circumstances, it is possible for cash to be held in abeyance for a non-U.S. holder until a pre-funded warrant is exercised or the ownership limitations (described under “Description of Pre-Funded Warrants” above) would not be exceeded, at which time the non-U.S. holder shall be entitled to receive distributions. It is possible that such entitlement to distributions could cause the declaration of a distribution on our common stock to be currently taxable to non-U.S. holders of pre-funded warrants, including under the principles governing Section 305 of the Code, even though such holders will not receive the distributions until a future date. Additionally, it is possible that other adjustments to the terms of the pre-funded warrant may be considered constructive distributions under Section 305 of the Code and taxable as discussed above. A non-U.S. holder of a pre-funded warrant should consult its tax advisor regarding the tax treatment of any distribution with respect to such pre-funded warrant that is held in abeyance in connection with any applicable limitation on the holder’s beneficial ownership of our common stock.

Gain on Sale or Other Disposition of Common Stock and Pre-Funded Warrants

Subject to the discussion below under the headings “FATCA” and “Backup Withholding, Information Reporting and Other Reporting Requirements,” a non-U.S. holder generally will not be subject to U.S. federal income tax on any gain realized upon the sale or other disposition of our common stock or pre-funded warrants unless:

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the gain is effectively connected with a trade or business carried on by the non-U.S. holder within the United States (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by such non-U.S. holder);

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the non-U.S. holder is an individual and is present in the United States for 183 days or more in the taxable year of disposition and certain other conditions are met; or

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we are or have been a “U.S. real property holding corporation” for U.S. federal income tax purposes at any time within the shorter of the five-year period preceding such disposition or such non-U.S. holder’s holding period of our common stock, and, provided that our common stock is regularly traded on an established securities market within the meaning of applicable Treasury Regulations, the non-U.S. holder has held, directly, indirectly, or constructively, at any time during said period, more than 5% of our common stock.

Gain that is effectively connected with the conduct of a trade or business in the United States generally will be subject to U.S. federal income tax on a net income tax basis, at regular U.S. federal income tax rates that apply to U.S. persons. If the non-U.S. holder is a non-U.S. corporation, the branch profits tax described above also may apply to such effectively connected gain. An individual non-U.S. holder who is subject to U.S. federal income tax because the non-U.S. holder was present in the United States for 183 days or more during the year of sale or other disposition of our common stock or pre-funded warrants will be subject to a flat 30% tax (or such lower rate as may be specified

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by an applicable income tax treaty) on the gain derived from such sale or other disposition, which may be offset by certain U.S.-source capital losses, if any. We believe that we are not and we do not anticipate becoming a U.S. real property holding corporation for U.S. federal income tax purposes. Non-U.S. holders should consult their tax advisors regarding potentially applicable income tax treaties that may provide for different rules.

FATCA

Withholding taxes may be imposed under the so-called Foreign Account Tax Compliance Act (“FATCA”), on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends (including deemed dividends) paid on our common stock or pre-funded warrants, to a “foreign financial institution” or a “non-financial foreign entity” (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any “substantial United States owners” (as defined in the Code) or furnishes identifying information regarding each substantial U.S. owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to the reporting rules of that intergovernmental agreement. Because we may not know the extent to which a distribution is a dividend for U.S. federal income tax purposes at the time it is made, for purposes of these withholding rules we or the applicable withholding agent may treat the entire distribution as a dividend. Although withholding under FATCA applies also to payments of gross proceeds from the sale or other disposition of stock on or after January 1, 2019, proposed Treasury Regulations would eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued. Under certain circumstances, a non-U.S. holder will be eligible for refunds or credits of withholding taxes imposed under FATCA by timely filing a U.S. federal income tax return. Prospective investors should consult their tax advisors regarding the potential application of these withholding provisions.

Backup Withholding, Information Reporting and Other Reporting Requirements

Annual reports are required to be filed with the IRS and provided to each non-U.S. holder indicating the amount of distributions on our common stock or pre-funded warrants paid to such holder and the amount of any tax withheld with respect to those distributions. These information reporting requirements apply regardless of whether such distributions constitute dividends and even if no withholding was required. This information also may be made available under a specific treaty or agreement with the tax authorities in the country in which the non-U.S. holder resides or is established. Backup withholding, currently at a 24% rate, generally will not apply to payments to a non-U.S. holder of dividends on or the gross proceeds of a disposition of our common stock or pre-funded warrants provided the non-U.S. holder furnishes the required certification for its non-U.S. status, such as by providing a valid IRS Form W-8BEN, IRS Form W-8BEN-E or IRS Form W-8ECI, or certain other requirements are met. Backup withholding may apply if the payor has actual knowledge, or reason to know, that the holder is a U.S. person who is not an exempt recipient.

Generally, information reporting and backup withholding will not apply to a payment of disposition proceeds to a non-U.S. holder where the transaction is effected outside the United States through a non-U.S. office of a broker. However, for information reporting purposes, dispositions effected through a non-U.S. office of a broker with substantial U.S. ownership or operations generally will be treated in a manner similar to dispositions effected through a U.S. office of a broker. Prospective investors should consult their own tax advisors regarding the application of the information reporting and backup withholding rules to them, including the availability of and procedure for obtaining an exemption from backup withholding.

Backup withholding is not an additional tax. If any amount is withheld under the backup withholding rules, the non-U.S. holder should consult with a U.S. tax advisor regarding the possibility of and procedure for obtaining a refund or a credit against the non-U.S. holder’s U.S. federal income tax liability, if any.

U.S. Federal Estate Tax

Our securities that are owned or treated as owned by an individual who is not a citizen or resident of the United States (as specially defined for U.S. federal estate tax purposes) at the time of death are considered U.S. situs assets and will be included in the individual’s gross estate for U.S. federal estate tax purposes. Such shares, therefore, may be subject to U.S. federal estate tax, unless an applicable estate tax or other treaty provides otherwise.

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The preceding discussion of material U.S. federal income tax considerations and certain U.S. federal estate tax considerations is for information only. It is not legal or tax advice. Prospective investors should consult their tax advisors regarding the particular U.S. federal, state, local and non-U.S. tax consequences of acquiring, owning and disposing of our securities, including the consequences of any proposed changes in applicable laws.

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DESCRIPTION OF PRE-FUNDED WARRANTS

The following is a brief summary of certain terms and conditions of the pre-funded warrants being offered by this prospectus supplement. The following description is subject in all respects to the provisions contained in the pre-funded warrants.

Form

The pre-funded warrants will be issued as individual warrant agreements to certain investors. The form of pre-funded warrant will be filed as an exhibit to our Current Report on Form 8-K that we expect to file with the SEC in connection with this offering.

Term

The pre-funded warrants will expire on the date the warrant is exercised in full.

Exercisability

The pre-funded warrants are exercisable at any time after their original issuance. The pre-funded warrants will be exercisable, at the option of each holder, in whole or in part by delivering to us a duly executed exercise notice and by payment in full of the exercise price in immediately available funds for the number of shares of our common stock purchased upon such exercise. As an alternative to payment in immediately available funds, the holder may, in its sole discretion, elect to exercise the pre-funded warrant through a cashless exercise, in which case the holder would receive upon such exercise, the net number of shares of our common stock determined according to the formula set forth in the pre-funded warrant. No fractional shares of our common stock will be issued in connection with the exercise of a pre-funded warrant. In lieu of any fractional shares, we will pay cash equal to the product of such fraction multiplied by the last trade price of our common stock on the exercise date.

Exercise Limitations

Under the pre-funded warrants, we may not effect the exercise of any pre-funded warrant, and a holder will not be entitled to exercise any portion of any pre-funded warrant, which, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by the holder (together with its affiliates) to exceed 4.99% or 9.99%, as the case may be, of the number of shares of our common stock outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the pre-funded warrants. However, any holder may increase or decrease such percentage to any other percentage not in excess of 19.99% upon at least 61 days’ prior notice from the holder to us.

Exercise Price

The exercise price per whole share of our common stock purchasable upon the exercise of the pre-funded warrants is $0.0001 per share of common stock. The exercise price of the pre-funded warrants and the number of shares of our common stock issuable upon exercise of the pre-funded warrants is subject to appropriate adjustment in the event of certain stock dividends, subdivisions, stock splits, stock combinations, reclassifications, reorganizations or similar events affecting our common stock.

Transferability

Subject to applicable laws and the restrictions on transfer set forth in the pre-funded warrants, the pre-funded warrants may be offered for sale, sold, transferred or assigned without our consent.

Exchange Listing

We do not plan on applying to list the pre-funded warrants on The Nasdaq Capital Market, any other national securities exchange or any other nationally recognized trading system.

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Fundamental Transactions

Upon the consummation of a fundamental transaction (as described in the pre-funded warrants, and generally including any reorganization, recapitalization or reclassification of our common stock, the sale, transfer or other disposition of all or substantially all of our assets, our consolidation or merger with or into another person in which we are not the surviving entity, the acquisition of more than 50% of our outstanding common stock, or any person or group becoming the beneficial owner of 50% of the voting power of our outstanding common stock), the holders of the pre-funded warrants will be entitled to receive, upon exercise of the pre-funded warrants, the same kind and amount of securities, cash or other property that such holders would have received had they exercised the pre-funded warrants immediately prior to such fundamental transaction, without regard to any limitations on exercise contained in the pre-funded warrants. Notwithstanding the foregoing, in the event of a fundamental transaction where the consideration consists solely of cash, then each pre-funded warrant shall automatically be deemed to be exercised in full in a cashless exercise effective immediately prior to and contingent upon the consummation of such fundamental transaction.

No Rights as a Stockholder

Except by virtue of such holder’s ownership of shares of our common stock, the holder of a pre-funded warrant does not have the rights or privileges of a holder of our common stock, including any voting rights, until the holder exercises the pre-funded warrant. In the event of certain distributions, including cash dividends, if any, to all holders of our common stock for no consideration, the holder of a pre-funded warrant shall be entitled to participate in such distributions to the same extent as if a holder of shares of our common stock, subject to not exceeding the ownership limitations described above under “—Description of Pre-Funded Warrants—Exercise Limitations,” in which case such distribution shall be held in abeyance for the benefit of such holder until the earlier of such time as the ownership limitations would not be exceeded or the warrant is exercised.

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UNDERWRITING

Subject to the terms and conditions set forth in the underwriting agreement, dated March , 2026 between us and Jefferies LLC, UBS Securities LLC, Citigroup Global Markets, Inc. and Barclays Capital Inc., as the representatives of the underwriters named below and the joint book-running managers of this offering, we have agreed to sell to the underwriters, and each of the underwriters has agreed, severally and not jointly, to purchase from us, the respective number of shares of common stock and pre-funded warrants shown opposite its name below:


Underwriter	Number of Shares	Number of Pre-Funded Warrants
Jefferies LLC
UBS Securities LLC
Citigroup Global Markets, Inc
Barclays Capital Inc.
Chardan Capital Markets LLC
Total

The underwriting agreement provides that the obligations of the several underwriters are subject to certain conditions precedent such as the receipt by the underwriters of officers’ certificates and legal opinions and approval of certain legal matters by their counsel. The underwriting agreement provides that the underwriters will purchase all of the shares of common stock and pre-funded warrants. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the nondefaulting underwriters may be increased or the underwriting agreement may be terminated. We have agreed to indemnify the underwriters and certain of their controlling persons against certain liabilities, including liabilities under the Securities Act, and to contribute to payments that the underwriters may be required to make in respect of those liabilities.

The underwriters have advised us that, following the completion of this offering, they currently intend to make a market in the common stock as permitted by applicable laws and regulations. However, the underwriters are not obligated to do so, and the underwriters may discontinue any market-making activities at any time without notice in their sole discretion. Accordingly, no assurance can be given as to the liquidity of the trading market for the common stock, that you will be able to sell any of the common stock held by you at a particular time or that the prices that you receive when you sell will be favorable.

The underwriters are offering the shares of common stock and pre-funded warrants subject to their acceptance of the shares of common stock and pre-funded warrants from us and subject to prior sale. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

Commission and Expenses

The underwriters have advised us that they propose to offer the shares of common stock and pre-funded warrants to the public at the public offering price set forth on the cover page of this prospectus supplement and to certain dealers, which may include the underwriters, at that price less a concession not in excess of $ per share of common stock or pre-funded warrant. The underwriters may allow, and certain dealers may reallow, a discount from the concession to certain brokers and dealers. After the offering, the public offering price, concession and reallowance to dealers may be reduced by the representatives. No such reduction will change the amount of proceeds to be received by us as set forth on the cover page of this prospectus supplement.

The following table shows the public offering price, the underwriting discounts and commissions that we are to pay the underwriters and the proceeds, before expenses, to us in connection with this offering. Such amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares.

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	Per Share			Total
	Without	With		Without	With
	Option to Purchase Additional Shares	Option to Purchase Additional Shares	Per Pre-Funded Warrant	Option to Purchase Additional Shares	Option to Purchase Additional Shares
Public offering price	$	$	$	$	$
Underwriting discounts and commissions paid by us	$	$	$	$	$
Proceeds to us, before expenses	$	$	$	$	$

We estimate expenses payable by us in connection with this offering, other than the underwriting discounts and commissions referred to above, will be approximately $ .

Listing

Our common stock is listed on The Nasdaq Capital Market under the symbol “SABS.”

There is no established trading market for the pre-funded warrants, and we do not expect a market to develop. We do not intend to list the pre-funded warrants on any national securities exchange or nationally recognized trading system.

Stamp Taxes

If you purchase shares of common stock or pre-funded warrants offered in this prospectus supplement, you may be required to pay stamp taxes and other charges under the laws and practices of the country of purchase, in addition to the offering price listed on the cover page of this prospectus supplement.

Option to Purchase Additional Shares

We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase, from time to time, in whole or in part, up to an aggregate of shares from us at the public offering price set forth on the cover page of this prospectus supplement, less underwriting discounts and commissions. If the underwriters exercise this option, each underwriter will be obligated, subject to specified conditions, to purchase a number of additional shares proportionate to that underwriter’s initial purchase commitment as indicated in the table above.

No Sales of Similar Securities

We, our executive officers and directors have agreed, subject to specified exceptions, not to directly or indirectly:

•

sell, offer, contract or grant any option to sell (including any short sale), pledge, transfer, establish an open “put equivalent position” within the meaning of Rule 16a-l(h) under the Securities Exchange Act of 1934, as amended, or

•

otherwise dispose of any shares of common stock, options or warrants to acquire shares of common stock, or securities exchangeable or exercisable for or convertible into shares of common stock currently or hereafter owned either of record or beneficially, or

•

publicly announce an intention to do any of the foregoing,

for a period of 60 days after the date of this prospectus supplement without the prior written consent of the representatives.

This restriction terminates after the close of trading of the common stock on and including the 60th day after the date of this prospectus supplement.

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With respect to the Company, this restriction does not apply to (A) the transactions contemplated by this offering, (B) the issuance by us of common stock or options to purchase common stock, or the issuance of common stock upon exercise of options, pursuant to stock options, stock bonuses or other stock plans or arrangements described in the registration statement of which this prospectus supplement forms a part, (C) the issuance by us of common stock pursuant to the conversion of securities or the exercise of warrants, which securities or warrants are outstanding as of the date hereof, but with respect to clauses (A) through (C), only if the holders of such shares of common stock or options agree in writing with the underwriters not to sell, offer, dispose of or otherwise transfer any such shares of common stock or options during the lock-up period without the prior written consent of the representatives (which consent may be withheld in their sole discretion), (D) file a registration statement on Form S-8 under the Securities Act to register the offer and sale of securities to be issued pursuant to any existing equity incentive plan, (E) the adoption of a new equity incentive plan, including an inducement plan, and filing of a registration statement on Form S-8 under the Securities Act to register the offer and sale of securities to be issued pursuant to such new equity incentive plan, subject to certain limitations, (F) the issuance by us of shares of our common stock or related securities not exceeding, in the aggregate, that number of shares equal to five percent (5%) of our outstanding shares at the time immediately after the first closing date, on an arm’s-length basis, to one or more counterparties in connection with the consummation of a strategic partnership, joint venture, collaboration, merger, co-promotion or distribution arrangement, or the acquisition, in-licensing or out-licensing of any business products or technologies, and that prior to any issuance under this clause (F), each recipient of such shares of common stock or related securities shall execute a lock-up agreement, and (G) the issuance of shares of common stock pursuant to the at the market sales agreement with UBS Securities LLC or any replacement “at the market” offering program, provided that no such sales shall be made prior to the expiration of the underwriters’ option to purchase additional shares, unless the option has been fully exercised by the underwriters and all optional shares have been issued by the Company.

Notwithstanding the foregoing, our executive officers and directors may transfer shares of common stock (i) by gift, or by will or intestate succession to a family member or to a trust whose beneficiaries consist exclusively of one or more of the securityholder and/or a family member, (ii) as a bona fide gift to a charity or educational institution, (iii) transfers that occur solely by operation of law pursuant to pursuant to a court order, qualified domestic order or in connection with a divorce settlement, (iv) acquired in open market transactions after the completion of the offering, provided that no filing under Section 16(a) of the Exchange Act shall be required or shall be voluntarily made in connection with subsequent sales of shares or related securities acquired in such open market transactions, or (vii) the transfer of shares in connection with the exercise, including by and to the extent necessary to cover any “net” or “cashless” exercise, of any options or warrants to acquire shares or the conversion of any convertible security into shares in accordance with its terms; provided, in the case of clauses (i)-(iii) above, each transferee executes and delivers an agreement stating that such transferee is receiving and holding such shares and/or related securities subject to the provisions of the lock-up agreement and in the case of clauses (i)-(iii) and (v), prior to the expiration of the lock-up period, no public disclosure or filing under the Exchange Act by any party to the transfer (donor, donee, transferor or transferee) shall be required, or made voluntarily, reporting a reduction in beneficial ownership of shares in connection with such transfer; provided that if the securityholder is required to file a report under Section 13 or Section 16(a) of the Exchange Act reporting a reduction in beneficial ownership during the lock-up period, the securityholder shall include a statement in such report detailing the reason for the transaction.

The representatives may, in their sole discretion and at any time or from time to time before the termination of the 60-day period release all or any portion of the securities subject to lock-up agreements. There are no existing agreements between the underwriters and any of our shareholders who will execute a lock-up agreement, providing consent to the sale of shares prior to the expiration of the lock-up period.

Stabilization

The underwriters have advised us that they, pursuant to Regulation M under the Exchange Act, certain persons participating in the offering may engage in short sale transactions, stabilizing transactions, syndicate covering transactions or the imposition of penalty bids in connection with this offering. These activities may have the effect of stabilizing or maintaining the market price of the common stock at a level above that which might otherwise prevail in the open market. Establishing short sales positions may involve either “covered” short sales or “naked” short sales.

“Covered” short sales are sales made in an amount not greater than the underwriters’ option to purchase additional shares of our common stock in this offering. The underwriters may close out any covered short position by either

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exercising their option to purchase additional shares of our common stock or purchasing shares of our common stock in the open market. In determining the source of shares to close out the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the option to purchase additional shares.

“Naked” short sales are sales in excess of the option to purchase additional shares of our common stock. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the shares of our common stock in the open market after pricing that could adversely affect investors who purchase in this offering.

A stabilizing bid is a bid for the purchase of shares of common stock on behalf of the underwriters for the purpose of fixing or maintaining the price of the common stock. A syndicate covering transaction is the bid for or the purchase of shares of common stock on behalf of the underwriters to reduce a short position incurred by the underwriters in connection with the offering. Similar to other purchase transactions, the underwriter’s purchases to cover the syndicate short sales may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock may be higher than the price that might otherwise exist in the open market. A penalty bid is an arrangement permitting the underwriters to reclaim the selling concession otherwise accruing to a syndicate member in connection with the offering if the common stock originally sold by such syndicate member are purchased in a syndicate covering transaction and therefore have not been effectively placed by such syndicate member.

Neither we nor any of the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common stock. The underwriters are not obligated to engage in these activities and, if commenced, any of the activities may be discontinued at any time.

The underwriters may also engage in passive market making transactions in our common stock on The Nasdaq Capital Market in accordance with Rule 103 of Regulation M during a period before the commencement of offers or sales of shares of our common stock in this offering and extending through the completion of distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker’s bid, that bid must then be lowered when specified purchase limits are exceeded.

Electronic Distribution

This prospectus supplement and the accompanying prospectus in electronic format may be made available by e-mail or on the web sites or through online services maintained by one or more of the underwriters or their affiliates. In those cases, prospective investors may view offering terms online and may be allowed to place orders online. The underwriters may agree with us to allocate a specific number of shares of common stock for sale to online brokerage account holders. Any such allocation for online distributions will be made by the underwriters on the same basis as other allocations. Other than the prospectus supplement in electronic format, the information on the underwriters’ web sites and any information contained in any other web site maintained by any of the underwriters is not part of this prospectus supplement, has not been approved and/or endorsed by us or the underwriters and should not be relied upon by investors.

Other Activities and Relationships

The underwriters and certain of their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters and certain of their respective affiliates have, from time to time, performed, and may in the future perform, various commercial and investment banking and financial advisory services for us and our affiliates, for which they received or will receive customary fees and expenses.

In the ordinary course of their various business activities, the underwriters and certain of their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments issued by us and

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our affiliates. If the underwriters or their respective affiliates have a lending relationship with us, they routinely hedge their credit exposure to us consistent with their customary risk management policies. The underwriters and their respective affiliates may hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities or the securities of our affiliates, including potentially the common stock offered hereby. Any such short positions could adversely affect future trading prices of the common stock offered hereby. The underwriters and certain of their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Notice to Prospective Investors in the European Economic Area

In relation to each Member State of the European Economic Area and the United Kingdom (each, a “Relevant State”), no shares or pre-funded warrants have been offered or will be offered pursuant to the offering to the public in that Relevant State prior to the publication of a prospectus in relation to the shares or pre-funded warrants which has been approved by the competent authority in that Relevant State or, where appropriate, approved in another Relevant State and notified to the competent authority in that Relevant State, all in accordance with the Prospectus Regulation, except that offers of shares or pre-funded warrants may be made to the public in that Relevant State at any time under the following exemptions under the Prospectus Regulation:

(a)

to any legal entity which is a qualified investor as defined under the Prospectus Regulation;

(b)

to fewer than 150 natural or legal persons (other than qualified investors as defined under the Prospectus Regulation), subject to obtaining the prior consent of the representatives for any such offer; or

(c)

in any other circumstances falling within Article 1(4) of the Prospectus Regulation, provided that no such offer of shares or pre-funded warrants shall require us or any representative to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.

Each person in a Relevant State who initially acquires any shares or pre-funded warrants or to whom any offer is made will be deemed to have represented, acknowledged and agreed to and with us and the representatives that it is a qualified investor within the meaning of the Prospectus Regulation.

In the case of any shares or pre-funded warrants being offered to a financial intermediary as that term is used in Article 5(1) of the Prospectus Regulation, each such financial intermediary will be deemed to have represented, acknowledged and agreed that the shares or pre-funded warrants acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer to the public other than their offer or resale in a Relevant State to qualified investors, in circumstances in which the prior consent of the representatives has been obtained to each such proposed offer or resale.

We, the underwriters and their affiliates will rely upon the truth and accuracy of the foregoing representations, acknowledgements and agreements.

For the purposes of this provision, the expression an “offer to the public” in relation to any shares or pre-funded warrants in any Relevant State means the communication in any form and by any means of sufficient information on the terms of the offer and any shares or pre-funded warrants to be offered so as to enable an investor to decide to purchase or subscribe for any shares or pre-funded warrants, and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129.

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The above selling restriction is in addition to any other selling restrictions set out below.

In connection with the offering, the underwriters are not acting for anyone other than us and will not be responsible to anyone other than us for providing the protections afforded to their clients nor for providing advice in relation to the offering.

Notice to Prospective Investors in the United Kingdom

No shares of our common stock have been offered or will be offered pursuant to the offering to the public in the United Kingdom except that the shares of our common stock may be offered to the public in the United Kingdom at any time:

(a)

where (i) the offer is conditional on the admission of the shares of our common stock to trading on the London Stock Exchange plc’s main market (in reliance on the exception in paragraph 6(a) of Schedule 1 of the POATR) or (ii) the shares of our common stock being offered are at the time of the offer already admitted to trading on London Stock Exchange plc’s main market (in reliance on the exception in paragraph 6(b) of Schedule 1 of the POATR);

(b)

to any qualified investor as defined in paragraph 15 of Schedule 1 of the POATR;

(c)

to fewer than 150 persons (other than qualified investors as defined in paragraph 15 of Schedule 1 of the POATR), subject to obtaining the prior consent of the Global Co-ordinator for any such offer; or

(d)

in any other circumstances falling within Part 1 of Schedule 1 of the POATR.

For the purposes of this provision, the expression an “offer to the public” in relation to the shares of our common stock in the United Kingdom means the communication to any person which presents sufficient information on: (a) the shares of our common stock to be offered; and (b) the terms on which they are to be offered, to enable an investor to decide to buy or subscribe for the shares of our common stock and the expression “POATR” means the Public Offers and Admissions to Trading Regulations 2024.

Notice to Prospective Investors in Switzerland

We have not and will not register with the Swiss Financial Market Supervisory Authority (“FINMA”) as a foreign collective investment scheme pursuant to Article 119 of the Federal Act on Collective Investment Scheme of 23 June 2006, as amended (“CISA”), and accordingly the securities being offered pursuant to this prospectus supplement have not and will not be approved, and may not be licensable, with FINMA. Therefore, the securities have not been authorized for distribution by FINMA as a foreign collective investment scheme pursuant to Article 119 CISA and the securities offered hereby may not be offered to the public (as this term is defined in Article 3 CISA) in or from Switzerland. The securities may solely be offered to “qualified investors,” as this term is defined in Article 10 CISA, and in the circumstances set out in Article 3 of the Ordinance on Collective Investment Scheme of 22 November 2006, as amended (“CISO”), such that there is no public offer. Investors, however, do not benefit from protection under CISA or CISO or supervision by FINMA. This prospectus supplement and any other materials relating to the securities are strictly personal and confidential to each offeree and do not constitute an offer to any other person. This prospectus supplement may only be used by those qualified investors to whom it has been handed out in connection with the offer described in this prospectus supplement and may neither directly or indirectly be distributed or made available to any person or entity other than its recipients. It may not be used in connection with any other offer and shall in particular not be copied and/or distributed to the public in Switzerland or from Switzerland. This prospectus supplement does not constitute an issue prospectus as that term is understood pursuant to Article 652a and/or 1156 of the Swiss Federal Code of Obligations. We have not applied for a listing of the securities on the SIX Swiss Exchange or any other regulated securities market in Switzerland, and consequently, the information presented in this prospectus supplement does not necessarily comply with the information standards set out in the listing rules of the SIX Swiss Exchange and corresponding prospectus schemes annexed to the listing rules of the SIX Swiss Exchange

Notice to Prospective Investors in the Dubai International Financial Centre

This prospectus supplement relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (“DFSA”). This prospectus supplement is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other

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person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement nor taken steps to verify the information set forth herein and has no responsibility for the prospectus supplement. The shares and pre-funded warrants to which this prospectus supplement relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the shares or pre-funded warrants offered should conduct their own due diligence on the shares or pre-funded warrants. If you do not understand the contents of this prospectus supplement you should consult an authorized financial advisor.

Notice to Prospective Investors in Australia

No placement document, prospectus, product disclosure statement or other disclosure document has been lodged with the Australian Securities and Investments Commission (“ASIC”) in relation to the offering. This prospectus does not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (the “Corporations Act”), and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

Any offer in Australia of the shares or pre-funded warrants may only be made to persons (the “Exempt Investors”) who are “sophisticated investors” (within the meaning of section 708(8) of the Corporations Act), “professional investors” (within the meaning of section 708(11) of the Corporations Act) or otherwise pursuant to one or more exemptions contained in section 708 of the Corporations Act so that it is lawful to offer the shares or pre-funded warrants without disclosure to investors under Chapter 6D of the Corporations Act.

The shares or pre-funded warrants applied for by Exempt Investors in Australia must not be offered for sale in Australia in the period of 12 months after the date of allotment under the offering, except in circumstances where disclosure to investors under Chapter 6D of the Corporations Act would not be required pursuant to an exemption under section 708 of the Corporations Act or otherwise or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring shares or pre-funded warrants must observe such Australian on-sale restrictions.

This prospectus contains general information only and does not take account of the investment objectives, financial situation or particular needs of any particular person. It does not contain any securities recommendations or financial product advice. Before making an investment decision, investors need to consider whether the information in this prospectus supplement is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

Notice to Prospective Investors in Hong Kong

The shares and pre-funded warrants have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that Ordinance. No advertisement, invitation or document relating to the shares or pre-funded warrants has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to securities which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the Securities and Futures Ordinance and any rules made under that Ordinance.

Notice to Prospective Investors in Japan

The shares and pre-funded warrants have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948, as amended) and, accordingly, will not be offered or sold, directly or indirectly, in Japan, or for the benefit of any Japanese Person or to others for re-offering or resale, directly or indirectly, in Japan or to any Japanese Person, except in compliance with all applicable laws, regulations and ministerial guidelines promulgated by relevant Japanese governmental or regulatory authorities in effect at the

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relevant time. For the purposes of this paragraph, “Japanese Person” shall mean any person resident in Japan, including any corporation or other entity organized under the laws of Japan.

Notice to Prospective Investors in Singapore

This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, the shares and pre-funded warrants were not offered or sold or caused to be made the subject of an invitation for subscription or purchase and will not be offered or sold or caused to be made the subject of an invitation for subscription or purchase, and this prospectus supplement or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares or pre-funded warrants, has not been circulated or distributed, nor will it be circulated or distributed, whether directly or indirectly, to any person in Singapore other than (i) to an institutional investor (as defined in Section 4A of the Securities and Futures Act (Chapter 289) of Singapore, as modified or amended from time to time (the “SFA”)) pursuant to Section 274 of the SFA, (ii) to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares or pre-funded warrants are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

(a)

a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

(b)

a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor,

securities or securities-based derivatives contracts (each term as defined in Section 2(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares or pre-funded warrants pursuant to an offer made under Section 275 of the SFA except:

(a)

to an institutional investor or to a relevant person, or to any person arising from an offer referred to in Section 275(1A) or Section 276(4)(i)(B) of the SFA;

(b)

where no consideration is or will be given for the transfer;

(c)

where the transfer is by operation of law; or

(d)

(d) as specified in Section 276(7) of the SFA.

Notice to Prospective Investors in Canada

The shares and pre-funded warrants may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the shares or pre-funded warrants must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 (or, in the case of securities issued or guaranteed by the government of a non-Canadian jurisdiction, section 3A.4) of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

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LEGAL MATTERS

The validity of the securities being offered by this prospectus supplement will be passed upon for us by Dentons US LLP, New York, New York. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts, is counsel to the underwriters in connection with this offering.

EXPERTS

The consolidated financial statements of SAB Biotherapeutics, Inc. as of and for the years ended December 31, 2025 and 2024, included in our Annual Report on Form 10-K for the year ended December 31, 2025, have been audited by EisnerAmper LLP, independent registered public accounting firm, as set forth in their report, and have been incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus supplement is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov.

You may also access our SEC filings at our website www.sab.bio. Our website and the information contained on, or that can be accessed through, our website will not be deemed to be incorporated by reference in, and are not considered part of, this prospectus. You should not rely on our website or any such information in making your decision whether to purchase our securities.

INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to incorporate by reference into this prospectus the information contained in other documents we file with the SEC, which means that we can disclose important information to you by referring you to those documents. Any statement contained in any document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded, for purposes of this prospectus, to the extent that a statement contained in or omitted from this prospectus, or in any other subsequently filed document that also is or is deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus. We incorporate by reference the documents listed below which have been filed by us:

•

our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the SEC on March 9, 2026;

•

the Current Report on Form 8-K filed with the SEC on January 7, 2026 and March 10, 2026; and

•

the description of our common stock and warrants in our registration statement on Form 8-A filed with the SEC on January 8, 2021, including any amendments or reports filed for the purpose of updating such description.

In addition, all documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act on or after the date of this prospectus and prior to the termination of the offering of the securities to which this prospectus relates, shall be deemed to be incorporated by reference in this prospectus and to be a part hereof from the date of filing of such documents. However, any documents or portions thereof, whether specifically listed above or filed in the future, that are not deemed “filed” with the SEC, including without limitation any information

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furnished pursuant to Item 2.02 or 7.01 of Form 8-K or certain exhibits furnished pursuant to Item 9.01 of Form 8-K, shall not be deemed to be incorporated by reference in this prospectus.

Any statement in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for the purposes of this prospectus to the extent that a statement contained herein or in any other subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

SAB Biotherapeutics, Inc.

777 W 41st St., Suite 401

Miami Beach, Florida 33140

Attn: Corporate Secretary

(305)-845-2813

In addition, you may obtain a copy of these filings from the SEC, as described in the section entitled “Where You Can Find More Information” in this prospectus supplement.

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PROSPECTUS

$300,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Rights

Units

From time to time, we may offer and sell up to an aggregate of $300,000,000 of any combination of the securities described in this prospectus, either individually or in combination. We may also offer common stock or preferred stock upon conversion of debt securities, common stock upon conversion of preferred stock, or common stock, preferred stock or debt securities upon the exercise of warrants. We may also issue units comprised of one or more shares of common stock, shares of preferred stock, debt securities, warrants and/or rights in any combination.

When we decide to sell particular securities, we will provide you with the specific terms and the offering price of the securities we are then offering in one or more prospectus supplements to this prospectus. The prospectus supplement may add to, change or update information contained in this prospectus. The prospectus supplement may also contain important information about U.S. federal income tax consequences. You should carefully read this prospectus, together with any prospectus supplements and information incorporated by reference in this prospectus and any prospectus supplements, before you decide to invest. This prospectus may not be used to offer or sell any securities unless accompanied by a prospectus supplement.

Our common stock is quoted on The Nasdaq Capital Market under the trading symbol “SABS.” Any common stock sold pursuant to this prospectus or any prospectus supplement will be listed on that exchange, subject to official notice of issuance. Each prospectus supplement to this prospectus will contain information, where applicable, as to any other listing on any national securities exchange of the securities covered by the prospectus supplement. On December 26, 2025, the last reported sale price of our common stock was $3.78 per share.

We may offer and sell the securities described in this prospectus to or through one or more underwriters, dealers or agents, or directly to purchasers on an immediate, continuous or delayed basis. The names of any underwriters, dealers or agents involved in the sale of any securities, the specific manner in which they may be offered and any applicable commissions or discounts will be set forth in an accompanying prospectus supplement covering the sales of those securities.

We are an “emerging growth company” as defined in Section 2(a) of the Securities Act of 1933, as amended the “Securities Act”) and a “smaller reporting company” as defined under Rule 405 of the Securities Act, and as such, we have elected to comply with certain reduced public company reporting requirements. See “Prospectus Summary— Implications of Being an Emerging Growth Company and a Smaller Reporting Company” on page of this prospectus

Investing in our securities involves significant risks. We strongly recommend that you read carefully the risks we describe in this prospectus and in any accompanying prospectus supplement, as well as the risk factors that are incorporated by reference into this prospectus from our filings made with the Securities and Exchange Commission. See “Risk Factors” beginning on page of this prospectus.

We may sell the securities directly or to or through underwriters or dealers, and also to other purchasers or through agents. The names of any underwriters or agents that are included in a sale of securities to you, and any applicable commissions or discounts, will be stated in an accompanying prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is January 7, 2026



TABLE OF CONTENTS
		Page
ABOUT THIS PROSPECTUS		1
TRADEMARKS		1
PROSPECTUS SUMMARY		2
SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS		4
RISK FACTORS		6
USE OF PROCEEDS		7
DESCRIPTION OF CAPITAL STOCK WE MAY OFFER		8
DESCRIPTION OF DEBT SECURITIES WE MAY OFFER		12
DESCRIPTION OF WARRANTS WE MAY OFFER		19
DESCRIPTION OF RIGHTS WE MAY OFFER		21
DESCRIPTION OF UNITS WE MAY OFFER		22
PLAN OF DISTRIBUTION		24
EXPERTS		25
LEGAL MATTERS		25
WHERE YOU CAN FIND MORE INFORMATION		25
INFORMATION INCORPORATED BY REFERENCE		27

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission (the “SEC”) using a “shelf” registration process. Under this shelf registration process, we may, from time to time, offer and sell common stock, preferred stock, debt securities, warrants for debt and equity securities, rights to purchase common stock, preferred stock, or warrants in one or more series, and units consisting of the foregoing in one or more transactions.

This prospectus only provides you with a general description of the securities we may sell in these transactions. Each time we sell any securities under this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement also may add, update or change information contained in this prospectus. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. This prospectus does not contain all of the information included in the registration statement we filed with the SEC. For further information about us or the securities offered hereby, you should carefully read this prospectus, any applicable prospectus supplement, any related free writing prospectuses, the information and documents incorporated herein by reference and the additional information under the heading “Where You Can Find Additional Information” before making an investment decision.

The exhibits to the registration statement of which this prospectus is a part contain the full text of certain contracts and other important documents we have summarized in this prospectus. Because these summaries may not contain all the information that you may find important in deciding whether to purchase the securities we may offer, you should review the full text of these documents. The registration statement and the exhibits can be obtained from the SEC as indicated under the heading “Where You Can Find Additional Information” below.

You should rely only on the information contained or incorporated by reference in this prospectus, any applicable prospectus supplement and any related free writing prospectuses that we may authorize to be provided to you. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus and the accompanying supplement to this prospectus are not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus, any applicable prospectus supplement or any related free writing prospectuses, as well as information we have previously filed with the SEC and incorporated by reference, is accurate only as of the date on the cover of those documents. If any statement in one of these documents is inconsistent with a statement in another document having a later date-for example, a document incorporated by reference in this prospectus-the statement in the document having the later date modifies or supersedes the earlier statement as our business, financial condition, results of operations and prospects may have changed since the earlier dates.

This prospectus may not be used to consummate sales of any of these securities unless it is accompanied by a prospectus supplement. To the extent there are inconsistencies between any prospectus supplement, this prospectus and/or any documents incorporated by reference, the document with the most recent date will control.

In this prospectus and any prospectus supplement, unless the context suggests otherwise, references to “SAB Biotherapeutics,” “SAB,” the “Company,” “we,” “us” and “our” refer to SAB Biotherapeutics, Inc.

TRADEMARKS

We and our subsidiaries own or have rights to trademarks, trade names and service marks that they use in connection with the operation of their business. In addition, their names, logos and website names and addresses are their trademarks or service marks. Other trademarks, trade names and service marks appearing in this prospectus are the property of their respective owners. Solely for convenience, in some cases, the trademarks, trade names and service marks referred to in this prospectus are listed without the applicable ®, ™ and SM symbols, but they will assert, to the fullest extent under applicable law, their rights to these trademarks, trade names and service marks.

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PROSPECTUS SUMMARY

This summary highlights selected information appearing elsewhere in this prospectus, or incorporated by reference into this prospectus, and does not contain all of the information that you should consider in making your investment decision. You should carefully read this entire prospectus, the applicable prospectus supplement and any free writing prospectus, including the risks of investing in our securities discussed under the heading “Risk Factors” on page of this prospectus and contained in our filings made with the SEC and any applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus.

Business Overview

We are a clinical-stage biopharmaceutical company focused on developing multi-specific, high-potency, human immunoglobulin G (“hIgGs”), without the need for human donors or convalescent plasma, to treat and prevent autoimmune disorders. Our programs are based on mechanisms of action that have achieved proof-of-concept in clinical trials in indications with significant unmet medical needs. We are focused on developing product candidates for disease targets where a differentiated approach has the greatest potential to be either first-in-class against novel targets or best-in-class against complex targets to treat diseases, including type 1 diabetes (“T1D”) and other autoimmune disorders. Our internally discovered antibodies are multi-specific, meaning they are comprised of multiple hIgG and can bind to multiple sites on targeted immunogens, making them ideally suited to address the complexities associated with many immune-mediated disorders. Our proprietary platform holds the potential to generate additional novel therapeutic candidates to expand our pipeline, utilizing the human immune response to generate the optimal repertoire of hIgG for drug targets of interest. We believe it is the only technology capable of producing disease-targeted, hIgG in large quantities without the need for human plasma donors. We have optimized genetic engineering in the development of transchromosomic cattle, or Tc Bovine, which produce hIgG. Our engineering of our production platform drives IgG1 production across our pipeline. In addition, this differentiated approach using polyclonal antibodies has no biosimilar pathway, which provides a significant barrier to competitive polyclonal approaches.

SAB-142: Our Lead Product Candidate

Our wholly owned lead product candidate, SAB-142 is a human anti-thymocyte globulin (“hATG”) focused on preventing or delaying the progression of Stage 3 T1D. SAB-142 is a first-in-class, multi-target hATG treatment designed to provide superior efficacy and safety in delaying the onset or progression of T1D. SAB-142 is expected to reduce autoimmune β-cell destruction and delay progression or onset of T1D in patients with Stage 3 or Stage 2 T1D, respectively. The mechanism of action of SAB-142 has been clinically validated in numerous clinical trials with a rabbit anti-thymocyte globulin (“rATG”), and rATG has demonstrated in multiple clinical trials the ability to slow disease progression in patients with new or recent onset of Stage 3 T1D. In addition, data from more than 700 human subjects treated with antibodies produced by our platform support the expectation of a zero-serum sickness rate and a zero incidence of neutralizing anti-drug antibodies (“ADA”) within the upcoming SAB-142 clinical trials.

We received an Investigational New Drug (“IND”) clearance from the FDA in May 2024 and announced positive topline data from our Phase 1 clinical trial of SAB-142 in January 2025. We are advancing SAB-142 into a Phase 2b clinical trial called the SAFEGUARD study. On May 29, 2025, the Company held a constructive Type B meeting with the FDA. The meeting followed positive topline data from a Phase 1 single-ascending dose trial in healthy volunteers for SAB-142. The primary discussion centered on questions related to all aspects of SAB-142’s Phase 2b SAFEGUARD clinical trial design and chemistry, manufacturing, and controls processes. The FDA provided clear, constructive, and actionable guidance during the discussion leading to alignment on the design and advancement of our Phase 2b SAFEGUARD study. SAB confirmed its intent with the FDA to utilize the data from this study as supportive evidence for future regulatory approval.

Other Immunology Indications

T- and B-cells are multifunctional lymphocytes whose dysregulation was shown to have a central role in the pathogenesis of more than 80 autoimmune diseases, including T1D, systemic lupus erythematosus (“SLE”), rheumatoid arthritis (“RA”), multiple sclerosis (“MS”) and celiac disease. The therapeutic success to date of lymphocyte-mediating therapies in variety of autoimmune diseases and our in vivo and in vitro pre-clinical and

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Phase 1 work from SAB-142 in T1D will support direct progression into Phase 2 clinical trials in other autoimmune indications.

Since the commencement of our operations, we have devoted substantially all of our resources to research and development activities, organizing and staffing our company, business planning, raising capital, establishing and maintaining our intellectual property portfolio, conducting preclinical studies and clinical trials and providing general and administrative support for these operations.

Corporate Information

Implications of Being an Emerging Growth Company and a Smaller Reporting Company

We are also a “smaller reporting company” as defined under the Securities Act and the Securities Exchange Act of 1934, as amended (the “Exchange Act”). We may continue to be a smaller reporting company so long as either (i) the market value of shares of our common stock held by non-affiliates is less than $250 million or (ii) our annual revenue was less than $100 million during the most recently completed fiscal year and the market value of shares of our common stock held by non-affiliates is less than $700 million. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and have reduced disclosure obligations regarding executive compensation, and, similar to emerging growth companies, if we are a smaller reporting company under the requirements of (ii) above, we would not be required to obtain an attestation report on internal control over financial reporting issued by our independent registered public accounting firm.

Securities We May Offer Under This Prospectus

We may offer shares of our common stock and preferred stock, various series of debt securities and/or warrants to purchase any of such securities, either individually or in combination, up to a total dollar amount of $300,000,000, from time to time under this prospectus, together with the applicable prospectus supplement and any related free writing prospectus, at prices and on terms to be determined by market conditions at the time of any offering. We may also offer common stock, preferred stock and/or debt securities upon the exercise of warrants, and we may offer common stock or preferred stock upon the conversion of preferred stock or debt securities. This prospectus provides you with a general description of the securities we may offer. Each time we offer a type or series of securities under

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this prospectus, we will provide a prospectus supplement that will describe the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

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designation or classification;

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aggregate principal amount or aggregate offering price;

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maturity date, if applicable;

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original issue discount, if any;

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rates and times of payment of interest or dividends, if any;

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redemption, conversion, exercise, exchange or sinking fund terms, if any;

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conversion or exchange prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in the conversion or exchange prices or rates and in the securities or other property receivable upon conversion or exchange;

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ranking;

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restrictive covenants, if any;

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voting or other rights, if any;

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material or special U.S. federal income tax considerations, if any.

The applicable prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change any of the information contained in this prospectus or in the documents we have incorporated by reference. However, no prospectus supplement or free writing prospectus will offer a security that is not registered and described in this prospectus at the time of the effectiveness of the registration statement of which this prospectus is a part.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and certain information incorporated herein by reference contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those discussed in the forward-looking statements. The statements contained in this prospectus that are not purely historical are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Forward-looking statements are often identified by the use of words such as, but not limited to, “anticipate,” “believe,” “can,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “project,” “seek,” “should,” “strategy,” “target,” “will,” “would” and similar expressions or variations intended to identify forward-looking statements. These statements are based on the beliefs and assumptions of our management based on information currently available to management. Such forward-looking statements are subject to risks, uncertainties and other important factors that could cause actual results and the timing of certain events to differ materially from future results expressed or implied by such forward-looking statements.

Factors that might cause these differences include the following:

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our ability to recruit and enroll suitable patients in our clinical trials;

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the potential indications, attributes and benefits of our product candidates;

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our ability to obtain and maintain regulatory approval for our product candidates, and any related restrictions, limitations or warnings in the label of an approved product candidate;

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our ability to obtain funding for our operations, including funding necessary to complete further development, approval and, if approved, commercialization of our product candidates;

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the period over which we anticipate our existing cash and cash equivalents will be sufficient to fund our operating expense and capital expenditure requirements;

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the potential for our business development efforts to maximize the potential value of our portfolio;

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our ability to identify, in-license or acquire additional product candidates;

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our ability to compete with other companies currently marketing or engaged in the development of treatments for the indications that we are pursuing for our product candidates;

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our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates and the duration of such protection;

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our ability to contract with and rely on third parties to assist in conducting our clinical trials and manufacturing our product candidates;

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our manufacturing capabilities, third-party contractor capabilities and strategy;

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our plans related to manufacturing, supply and other collaborative agreements;

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the size and growth potential of the markets for our product candidates, and our ability to serve those markets, either alone or in partnership with others;

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the rate and degree of market acceptance of our product candidates, if approved;

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the pricing and reimbursement of our product candidates, if approved;

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regulatory developments in the United States and foreign countries;

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the impact of laws, regulations, accounting standards, regulatory requirements, judicial decisions and guidance issued by authoritative bodies;

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our ability to attract and retain key scientific, medical, commercial or management personnel;

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our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

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our financial performance;

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our ability to maintain our listing on The Nasdaq Capital Market; and

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our ability to continue as a going concern.

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RISK FACTORS

Before you invest in any of the company’s securities, in addition to the other information in this prospectus and the applicable prospectus supplement, you should carefully consider (i) the risk factors contained in the Company’s most recent annual report on Form 10-K, which is incorporated by reference into this prospectus, (ii) all of the other information included or incorporated by reference in this prospectus, and (iii) the applicable prospectus supplement, as the same may be updated from time to time by the Company’s future filings under the Exchange Act.

The risks and uncertainties described herein are not the only ones facing the Company. Additional risks and uncertainties not presently known to the Company or that the Company currently deems immaterial may also impair its business or operations. Any adverse effect on the Company’s business, financial condition or operating results could result in a decline in the value of the securities and the loss of all or part of your investment. The prospectus supplement applicable to each series of securities the Company offers may contain a discussion of additional risks applicable to an investment in the Company and the securities the Company is offering under that prospectus supplement.

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USE OF PROCEEDS

Unless otherwise indicated in the prospectus supplement, we will use the net proceeds from the sale of securities offered by this prospectus for development and commercialization of product candidates, working capital, and general corporate purposes. In addition, we believe opportunities may exist from time to time to expand our current business through acquisitions or in-licenses of, or investments in, complementary companies, medicines, intellectual property or technologies. While we have no current agreements or commitments for any specific acquisitions, in-licenses or investments at this time, we may use a portion of the net proceeds for these purposes. As of the date of this prospectus, we have not identified any specific and material proposed uses of the anticipated proceeds.

Our expected use of net proceeds from the sale of any securities offered pursuant to the applicable prospectus supplement for such offering will vary depending on our then current intentions based upon our plans and business condition. As of the date of this prospectus, we cannot predict with certainty all of the particular uses for the net proceeds to be received upon the completion of any offering or the amounts that we will actually spend on any specific uses set forth above. The amounts and timing of our actual use of the net proceeds will vary depending on numerous factors, including the factors described under or referenced under the heading “Risk Factors” in this prospectus. As a result, unless otherwise specified in the prospectus supplement, our management will have broad discretion in its application of the net proceeds, and investors will be relying on our judgment in such application.

Pending use of net proceeds from the sale of securities offered by this prospectus and the applicable prospectus supplement for such sale, we may invest in short-term and intermediate-term interest-bearing obligations, investment-grade instruments, certificates of deposit or direct or guaranteed obligations of the U.S. government.

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DESCRIPTION OF CAPITAL STOCK WE MAY OFFER

The following description summarizes important terms of our capital stock. For a complete description, you should refer to our certificate of incorporation, as amended, and bylaws, which are incorporated by reference as exhibits to the registration statement of which this prospectus is a part, as well as the relevant portions of the Delaware General Corporation Law (the “DGCL”).

General

Our authorized capital stock consists of 800,000,000 shares of common stock, $0.0001 par value per share, and 10,000,000 shares of preferred stock, $0.0001 par value per share.

The following description of our common stock and preferred stock, together with the additional information included in any applicable prospectus supplements or related free writing prospectuses, summarizes the material terms and provisions of these types of securities, but it is not complete. For the complete terms of our common stock and preferred stock, please refer to our certificate of incorporation, as amended, and our bylaws that are incorporated by reference into the registration statement which includes this prospectus and, with respect to preferred stock, any certificate of designation that we may file with the SEC for a series of preferred stock we may designate, if any.

We will describe in a prospectus supplement or related free writing prospectuses, the specific terms of any common stock or preferred stock we may offer pursuant to this prospectus. If indicated in a prospectus supplement, the terms of such common stock or preferred stock may differ from the terms described below.

Common Stock

Voting Power

Except as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, the holders of common stock possess all voting power for the election of our directors and all other matters requiring stockholder action. Holders of common stock are entitled to one vote per share on matters to be voted on by stockholders.

Dividends

Holders of common stock will be entitled to receive such dividends, if any, as may be declared from time to time by our board of directors in its discretion out of funds legally available therefor. In no event will any stock dividends or stock splits or combinations of stock be declared or made on common stock unless the shares of common stock at the time outstanding are treated equally and identically.

Liquidation, Dissolution and Winding Up

In the event of our voluntary or involuntary liquidation, dissolution, distribution of assets or winding-up, the holders of the common stock will be entitled to receive an equal amount per share of all of our assets of whatever kind available for distribution to stockholders, after the rights of the holders of the preferred stock have been satisfied.

Preemptive or Other Rights

Our stockholders have no preemptive or other subscription rights and there are no sinking fund or redemption provisions applicable to common stock.

Election of Directors

Our board of directors is divided into three classes, Class I, Class II and Class III, with only one class of directors being elected in each year and each class serving a three-year term, except with respect to the election of directors at the special meeting held in connection with the Business Combination, Class I directors are elected to an initial one-year term (and three-year terms subsequently), the Class II directors are elected to an initial two-year term (and three-year terms subsequently) and the Class III directors are elected to an initial three-year term (and three-year

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terms subsequently). There is no cumulative voting with respect to the election of directors, with the result that the holders of more than 50% of the shares voted for the election of directors can elect all of the directors.

Preferred Stock

Our Amended and Restated Certificate of Incorporation provides that shares of preferred stock may be issued from time to time in one or more series. Our board of directors is authorized to fix the voting rights, if any, designations, powers and preferences, the relative, participating, optional or other special rights, and any qualifications, limitations and restrictions thereof, applicable to the shares of each series of preferred stock. The Board is able to, without stockholder approval, issue preferred stock with voting and other rights that could adversely affect the voting power and other rights of the holders of common stock and could have anti-takeover effects. The ability of our board of directors to issue preferred stock without stockholder approval could have the effect of delaying, deferring or preventing a change of control of the Company or the removal of existing management.

As of the date hereof, we have 29,091 shares of Series A Convertible Preferred Stock, par value $0.0001 per share(“Series A Preferred Stock”), issued and outstanding and 638,558 shares of Series B Convertible Preferred Stock, par value $0.0001 per share (“Series B Preferred Stock”), issued and outstanding. The Series A Preferred Stock and Series B Preferred Stock are not being offered herein.

Certain Anti-Takeover Provisions of Delaware Law

Special Meetings of Stockholders

Our Amended and Restated Bylaws provide that special meetings of our stockholders may be called only by a majority vote of the board of directors, by the Chairperson of the board of directors, or by the chief executive officer.

Advance Notice Requirements for Stockholder Proposals and Director Nominations

Our Amended and Restated Bylaws provide that stockholders seeking to bring business before our annual meeting of stockholders, or to nominate candidates for election as directors at our annual meeting of stockholders, must provide timely notice of their intent in writing. To be timely under our Amended and Restated Bylaws, a stockholder’s notice will need to be received by the company secretary at our principal executive offices not later than the close of business on the 90th day nor earlier than the open of business on the 120th day prior to the first anniversary of the preceding year’s annual meeting. Pursuant to Rule 14a-8 of the Exchange Act, proposals seeking inclusion in our annual proxy statement must comply with the notice periods contained therein. Our Amended and Restated Bylaws also specify certain requirements as to the form and content of a stockholders’ meeting. These provisions may preclude our stockholders from bringing matters before our annual meeting of stockholders or from making nominations for directors at our annual meeting of stockholders.

Authorized but Unissued Shares

Our authorized but unissued common stock and preferred stock are available for future issuances without stockholder approval and could be utilized for a variety of corporate purposes, including future offerings to raise additional capital, acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

Exclusive Forum Selection

The Amended and Restated Certificate of Incorporation provides that unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (subject to certain limited exceptions) shall be the sole and exclusive forum for any of the following claims (i) any derivative claim or cause of action brought on our behalf, (ii) any claim or cause of action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of the Company to the Company or to the Company’s stockholders, (iii) any claim or cause of action against us, our directors, officers or employees arising pursuant to any provision of the DGCL, the Amended and Restated Certificate of Incorporation or the Amended and Restated Bylaws, and (iv) any claim or cause of action against the Company or any director, officer or other employee of the Company governed by the

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internal affairs doctrine, in all cases to the fullest extent permitted by law and subject to the court’s having personal jurisdiction over the indispensable parties named as defendants. Any person or entity holding, owning or otherwise acquiring any interest in shares of capital stock of the Company shall be deemed to have notice of and to have consented to such provisions. If the claim is brought outside of Delaware, the stockholder asserting such claim will be deemed to have consented to service of process on such stockholder’s counsel, except with respect to claims: (A) as to which the Court of Chancery in the State of Delaware determines that there is an indispensable party not subject to the jurisdiction of the Court of Chancery (and the indispensable party does not consent to personal jurisdiction of the Court of Chancery within ten days following such determination), (B) which is vested in the exclusive jurisdiction of a court or forum other than the Court of Chancery, (C) for which the Court of Chancery does not have subject matter jurisdiction, or (D) any action arising under the Securities Act.

Although we believe these provisions benefit us by providing increased consistency in the application of Delaware law in the types of lawsuits to which they apply, a court may determine that these provisions are unenforceable, and to the extent they are enforceable, the provisions may have the effect of discouraging lawsuits against our directors and officers, although our stockholders will not be deemed to have waived our compliance with federal securities laws and the rules and regulations thereunder. Additionally, we cannot be certain that a court will decide that these provisions are either applicable or enforceable, and if a court were to find the choice of forum provisions contained in our Amended and Restated Certificate of Incorporation to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving such action in other jurisdictions, which could harm our business, operating results and financial condition.

Our Amended and Restated Certificate of Incorporation provides that the exclusive forum provision will be applicable to the fullest extent permitted by applicable law. Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder. As a result, the exclusive forum provision will not apply to suits brought to enforce any duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. Furthermore, Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder. Accordingly, both state and federal courts have jurisdiction to entertain such claims. To prevent having to litigate claims in multiple jurisdictions and the threat of inconsistent or contrary rulings by different courts, among other considerations, the Amended and Restated Certificate of Incorporation provides that the federal district courts of the United States will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act.

Section 203 of the Delaware General Corporation Law

We are subject to provisions of Section 203 of the DGCL regulating corporate takeovers under our Amended and Restated Certificate of Incorporation. This statute prevents certain Delaware corporations, under certain circumstances, from engaging in a “business combination” with:

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a stockholder who owns 15% or more of our outstanding voting stock (otherwise known as an “interested stockholder”);

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an affiliate of an interested stockholder; or

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an associate of an interested stockholder, for three years following the date that the stockholder became an interested stockholder.

A “business combination” includes a merger or sale of more than 10% of our assets. However, the above provisions of Section 203 do not apply if:

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our board of directors approves the transaction that made the stockholder an “interested stockholder,” prior to the date of the transaction

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after the completion of the transaction that resulted in the stockholder becoming an interested stockholder, that stockholder owned at least 85% of our voting stock outstanding at the time the transaction commenced, other than statutorily excluded shares of common stock; or

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on or subsequent to the date of the transaction, our initial business combination is approved by our board of directors and authorized at a meeting of our stockholders, and not by written consent, by an

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affirmative vote of at least two-thirds of the outstanding voting stock not owned by the interested stockholder.

Under certain circumstances, this provision will make it more difficult for a person who would be an “interested stockholder” to effect various business combinations with the Company for a three-year period. This provision may encourage companies interested in acquiring us to negotiate in advance with our board of directors because the stockholder approval requirement would be avoided if our board of directors approves either the business combination or the transaction which results in the stockholder becoming an interested stockholder. These provisions also may have the effect of preventing changes in our board of directors and may make it more difficult to accomplish transactions which stockholders may otherwise deem to be in their best interests.

Limitation on Liability and Indemnification of Directors and Officers

The Amended and Restated Certificate of Incorporation eliminates directors’ liability for monetary damages to the fullest extent permitted by applicable law. Our Amended and Restated Certificate of Incorporation requires the Company to indemnify and advance expenses to, to the fullest extent permitted by applicable law, its directors, officers and agents and prohibit any retroactive changes to the rights or protections or increase the liability of any director in effect at the time of the alleged occurrence of any act or omission to act giving rise to liability or indemnification. We believe these provisions in our Amended and Restated Certificate of Incorporation are necessary to attract and retain qualified persons as directors and officers. However, these provisions may discourage stockholders from bringing a lawsuit against our directors for breach of their fiduciary duty. These provisions also may have the effect of reducing the likelihood of derivative litigation against directors and officers, even though such an action, if successful, might otherwise benefit us and our stockholders. Furthermore, a stockholder’s investment may be adversely affected to the extent we pay the costs of settlement and damage awards against directors and officers pursuant to these indemnification provisions.

Transfer Agent

The transfer agent for our securities is Continental Stock Transfer & Trust Company. The transfer agent’s address is One State Street Plaza, 30th Floor New York, New York 10004.

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DESCRIPTION OF DEBT SECURITIES WE MAY OFFER

The following description, together with the additional information we include in any applicable prospectus supplements or free writing prospectuses, summarizes the material terms and provisions of the debt securities that we may offer under this prospectus. We may issue debt securities, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any future debt securities we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement or free writing prospectus. The terms of any debt securities we offer under a prospectus supplement may differ from the terms we describe below. Unless the context requires otherwise, whenever we refer to the “indentures,” we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue any senior debt securities under the senior indenture that we will enter into with the trustee named in the senior indenture. We will issue any subordinated debt securities under the subordinated indenture and any supplemental indentures that we will enter into with the trustee named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement, of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

The indentures will be qualified under the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act. We use the term “trustee” to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualified in their entirety by reference to, all of the provisions of the indenture and any supplemental indentures applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete indenture that contains the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our board of directors and set forth or determined in the manner provided in an officers’ certificate or by a supplemental indenture. Debt securities may be issued in separate series without limitation as to aggregate principal amount. We may specify a maximum aggregate principal amount for the debt securities of any series. We will describe in the applicable prospectus supplement the terms of the series of debt securities being offered, including:

•

the title;

•

the principal amount being offered and, if a series, the total amount authorized and the total amount outstanding;

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any limit on the amount that may be issued;

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whether or not we will issue the series of debt securities in global form, and, if so, the terms and who the depositary will be;

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the maturity date;

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whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a U.S. person for tax purposes, and whether we can redeem the debt securities if we have to pay such additional amounts;

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the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

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whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

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•

the terms of the subordination of any series of subordinated debt;

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the place where payments will be payable;

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restrictions on transfer, sale or other assignment, if any;

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our right, if any, to defer payment of interest and the maximum length of any such deferral period;

•

the date, if any, after which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

•

provisions for a sinking fund purchase or other analogous fund, if any, including the date, if any, on which, and the price at which we are obligated, pursuant thereto or otherwise, to redeem, or at the holder’s option, to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

•

provisions relating to modification of the terms of the security or the rights of the security holder;

•

whether the indenture will restrict our ability or the ability of our subsidiaries to:

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incur additional indebtedness;

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issue additional securities;

•

create liens;

•

pay dividends or make distributions in respect of our capital stock or the capital stock of our subsidiaries;

•

redeem capital stock;

•

place restrictions on our subsidiaries’ ability to pay dividends, make distributions or transfer assets;

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make investments or other restricted payments;

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sell, transfer or otherwise dispose of assets;

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enter into sale-leaseback transactions;

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engage in transactions with stockholders or affiliates;

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issue or sell stock of our subsidiaries;

•

effect a consolidation or merger;

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whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

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information describing any book-entry features;

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the applicability of the provisions in the indenture on discharge;

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whether the debt securities are to be offered at a price such that they will be deemed to be offered at an “original issue discount” as defined in paragraph (a) of Section 1273 of the Internal Revenue Code of 1986, as amended;

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the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;

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the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars; and

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any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants provided with respect to the debt securities, and any terms that may be required by us or advisable under applicable laws or regulations.

U.S. federal income tax consequences applicable to debt securities sold at an original issue discount will be described in the applicable prospectus supplement. In addition, U.S. federal income tax or other consequences applicable to any debt securities which are denominated in a currency or currency unit other than U.S. dollars may be described in the applicable prospectus supplement.

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Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement the terms under which a series of debt securities may be convertible into or exchangeable for our common stock, our preferred stock or other securities (including securities of a third party). We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock, our preferred stock or other securities (including securities of a third party) that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the indentures will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquiror of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate. If the debt securities are convertible into or exchangeable for our other securities or securities of other entities, the person with whom we consolidate or merge or to whom we sell all of our property must make provisions for the conversion of the debt securities into securities that the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Events of Default under the Indenture

Unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, the following are events of default under the indentures with respect to any series of debt securities that we may issue:

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if we fail to pay interest when due and payable and our failure continues for 90 days and the time for payment has not been extended;

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if we fail to pay the principal, premium or sinking fund payment, if any, when due and payable and the time for payment has not been extended;

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if we fail to observe or perform any other covenant contained in the debt securities or the indentures, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive notice from the trustee or we and the trustee receive notice from the holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and

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if specified events of bankruptcy, insolvency or reorganization occur.

We will describe in each applicable prospectus supplement any additional events of default relating to the relevant series of debt securities. If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default arises due to the occurrence of certain specified bankruptcy, insolvency or reorganization events, the unpaid principal, premium, if any, and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any such waiver shall cure the default or event of default.

Subject to the terms of the applicable indenture, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity or security satisfactory to it against any loss, liability or expense. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time,

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method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

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the direction so given by the holders is not in conflict with any law or the applicable indenture; and

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subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

The indentures provide that if an event of default has occurred and is continuing, the trustee will be required in the exercise of its powers to use the degree of care that a prudent person would use in the conduct of its own affairs. The trustee, however, may refuse to follow any direction that conflicts with law or the indenture, or that the trustee determines is unduly prejudicial to the rights of any other holder of the relevant series of debt securities, or that would involve the trustee in personal liability. Prior to taking any action under the indentures, the trustee will be entitled to indemnification against all costs, expenses and liabilities that would be incurred by taking or not taking such action.

A holder of the debt securities of any series will have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies only if:

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the holder has given written notice to the trustee of a continuing event of default with respect to that series;

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the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made a written request and such holders have offered reasonable indemnity to the trustee or security satisfactory to it against any loss, liability or expense to be incurred in compliance with instituting the proceeding as trustee; and

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the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 60 days after the notice, request and offer

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indentures.

The indentures provide that if a default occurs and is continuing and is actually known to a responsible officer of the trustee, the trustee must mail to each holder notice of the default within 45 days after it occurs, unless such default has been cured. Except in the case of a default in the payment of principal or premium of, or interest on, any debt security or certain other defaults specified in an indenture, the trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a trust committee of directors, or responsible officers of the trustee, in good faith determine that withholding notice is in the best interests of holders of the relevant series of debt securities.

Modification of Indenture; Waiver

Subject to the terms of the indenture for any series of debt securities that we may issue, we and the trustee may change an indenture without the consent of any holders with respect to the following specific matters:

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to fix any ambiguity, defect or inconsistency in the indenture;

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to comply with the provisions described above under “Consolidation, Merger or Sale”;

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to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act;

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to add to, delete from or revise the conditions, limitations and restrictions on the authorized amount, terms or purposes of issue, authentication and delivery of debt securities, as set forth in such indenture;

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to provide for the issuance of, and establish the form and terms and conditions of, the debt securities of any series as provided under “General,” to establish the form of any certifications required to be

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furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

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to evidence and provide for the acceptance of appointment hereunder by a successor trustee;

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to provide for uncertificated debt securities in addition to or in place of certificated debt securities and to make all appropriate changes for such purpose;

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to add such new covenants, restrictions, conditions or provisions for the protection of the holders, and to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred to us in the indenture; or

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to change anything that does not materially adversely affect the interests of any holder of debt securities of any series in any material respect; provided that any amendment made solely to conform the provisions of the indenture to the corresponding description of the debt securities contained in the applicable prospectus or prospectus supplement shall be deemed not to adversely affect the interests of the holders of such debt securities; provided further, that in connection with any such amendment we will provide the trustee with an officers’ certificate certifying that such amendment will not adversely affect the rights or interests of the holders of such debt securities.

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, unless we provide otherwise in the prospectus supplement applicable to a particular series of debt securities, we and the trustee may only make the following changes with the consent of each holder of any outstanding debt securities affected:

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extending the fixed maturity of the series of debt securities;

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reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any debt securities;

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reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver;

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changing any of our obligations to pay additional amounts;

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reducing the amount of principal of an original issue discount security or any other note payable upon acceleration of the maturity thereof;

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changing the currency in which any note or any premium or interest is payable;

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impairing the right to enforce any payment on or with respect to any note;

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adversely changing the right to convert or exchange, including decreasing the conversion rate or increasing the conversion price of, such note, if applicable;

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in the case of the subordinated indenture, modifying the subordination provisions in a manner adverse to the holders of the subordinated debt securities;

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if the debt securities are secured, changing the terms and conditions pursuant to which the debt securities are secured in a manner adverse to the holders of the secured debt securities;

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reducing the requirements contained in the applicable indenture for quorum or voting;

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changing any of our obligations to maintain an office or agency in the places and for the purposes required by the indentures; or

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modifying any of the above provisions set forth in this paragraph.

Discharge

Each indenture provides that, subject to the terms of the indenture and any limitation otherwise provided in the prospectus supplement applicable to a particular series of debt securities, we may elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

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•

replace stolen, lost or mutilated debt securities of the series;

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maintain paying agencies;

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hold monies for payment in trust;

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recover excess money held by the trustee;

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compensate and indemnify the trustee; and

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appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, and any premium and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company or another depositary named by us and identified in a prospectus supplement with respect to that series.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will impose no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

If we elect to redeem the debt securities of any series, we will not be required to:

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issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

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register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture and is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur. However, upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs.

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Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest payment.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that, unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement, we will designate the corporate trust office of the trustee in the City of New York as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of, or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Ranking Debt Securities

The subordinated debt securities will be unsecured and will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of subordinated debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

The senior debt securities will be unsecured and will rank equally in right of payment to all our other senior unsecured debt. The senior indenture does not limit the amount of senior debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

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DESCRIPTION OF WARRANTS WE MAY OFFER

We typically issue warrants to purchase shares of our common stock to investors as part of a financing transaction, or in connection with services rendered by placement agents and outside consultants.

We may issue warrants to purchase debt securities, preferred stock, common stock or any combination of the foregoing. We may issue warrants independently or together with any other securities we offer under a prospectus supplement. The warrants may be attached to or separate from the securities. We will issue each series of warrants under a separate warrant agreement to be entered into between a warrant agent and us. The warrant agent will act solely as our agent in connection with the warrants and will not have any obligations or relationship of agency or trust for or with holders or beneficial owners of warrants. The following outlines some of the general terms and provisions of the warrants that we may issue from time to time. When we issue warrants, we will provide the specific terms of the warrants and the applicable warrant agreement in a prospectus supplement and any related free writing prospectuses and such terms may differ from those described below. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement. The following description, and any description of the warrants included in a prospectus supplement, may not be complete and is subject to and qualified in its entirety by reference to the terms and provisions of the applicable warrant agreement.

Equity Warrants

We will describe in the applicable prospectus supplement and any related free writing prospectuses the terms of the preferred stock warrants or common stock warrants being offered, the warrant agreement relating to the preferred stock warrants or common stock warrants and the warrant certificates representing the preferred stock warrants or common stock warrants, including, as applicable:

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the title of the warrants;

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the securities for which the warrants are exercisable;

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the price or prices at which the warrants will be issued;

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if applicable, the number of warrants issued with each share of preferred stock or share of common stock;

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if applicable, the date on and after which the warrants and the related preferred stock or common stock will be separately transferable;

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the date on which the right to exercise the warrants will commence, and the date on which the right will expire;

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the maximum or minimum number of warrants which may be exercised at any time;

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any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

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information with respect to book-entry procedures, if any;

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a discussion of the material U.S. federal income tax considerations applicable to exercise of the warrants; and

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any other terms of the warrants, including terms, procedures and limitations relating to the exchange and exercise of the warrants.

Unless otherwise provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses, holders of equity warrants will not be entitled, by virtue of being such holders, to vote, consent, receive dividends, receive notice as stockholders with respect to any meeting of stockholders for the election of our directors or any other matter, or to exercise any rights whatsoever as stockholders.

Except as provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses, the exercise price payable and the number of shares of common stock or preferred stock

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purchasable upon the exercise of each warrant will be subject to adjustment in certain events, including the issuance of a stock dividend to holders of common stock or preferred stock or a stock split, reverse stock split, combination, subdivision or reclassification of common stock or preferred stock. In lieu of adjusting the number of shares of common stock or preferred stock purchasable upon exercise of each warrant, we may elect to adjust the number of warrants. Unless otherwise provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses, no adjustments in the number of shares purchasable upon exercise of the warrants will be required until all cumulative adjustments require an adjustment of at least 1% thereof. No fractional shares will be issued upon exercise of warrants, but we will pay the cash value of any fractional shares otherwise issuable. Notwithstanding the foregoing, except as otherwise provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses, in case of any consolidation, merger, or sale or conveyance of our property as an entirety or substantially as an entirety, the holder of each outstanding warrant will have the right to the kind and amount of shares of stock and other securities and property, including cash, receivable by a holder of the number of shares of common stock or preferred stock into which each warrant was exercisable immediately prior to the particular triggering event.

Debt Warrants

We will describe in the applicable prospectus supplement and any related free writing prospectuses the terms of the debt warrants being offered, the warrant agreement relating to the debt warrants and the debt warrant certificates representing the debt warrants, including, as applicable:

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the title of the debt warrants;

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the aggregate number of the debt warrants;

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the price or prices at which the debt warrants will be issued;

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the designation, aggregate principal amount and terms of the debt securities purchasable upon exercise of the debt warrants, and the procedures and conditions relating to the exercise of the debt warrants;

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the designation and terms of any related debt securities with which the debt warrants are issued, and the number of the debt warrants issued with each security;

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the date, if any, on and after which the debt warrants and the related debt securities will be separately transferable;

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the principal amount of debt securities purchasable upon exercise of each debt warrant, and the price at which the principal amount of the debt securities may be purchased upon exercise;

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the date on which the right to exercise the debt warrants will commence, and the date on which the right will expire;

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the maximum or minimum number of the debt warrants that may be exercised at any time;

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information with respect to book-entry procedures, if any;

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changes to or adjustments in the exercise price of the debt warrants;

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a discussion of the material U.S. federal income tax considerations applicable to the exercise of the debt warrants; and

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any other terms of the debt warrants and terms, procedures and limitations relating to the exercise of the debt warrants.

As may be permitted under the warrant agreement, holders may exchange debt warrant certificates for new debt warrant certificates of different denominations, and may exercise debt warrants at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement and any related free writing prospectuses. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the securities purchasable upon the exercise, and will not be entitled to payments of principal, premium or interest on the securities purchasable upon the exercise, of debt warrants.

Exercise of Warrants

Each warrant will entitle the holder of the warrant to purchase for cash at the exercise price provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses the

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principal amount of debt securities or shares of preferred stock or shares of common stock being offered. Holders may exercise warrants at any time up to the close of business on the expiration date provided in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses. After the close of business on the expiration date, unexercised warrants are void.

Holders may exercise warrants as described in the applicable warrant agreement and corresponding prospectus supplement or any free writing prospectuses relating to the warrants being offered. Upon receipt of payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable warrant agreement and corresponding prospectus supplement or any related free writing prospectuses, we will, as soon as practicable, forward the debt securities, shares of preferred stock or shares of common stock purchasable upon the exercise of the warrant. If less than all of the warrants represented by the warrant certificate are exercised, we will issue a new warrant certificate for the remaining warrants.

DESCRIPTION OF RIGHTS WE MAY OFFER

We may issue rights to purchase shares of our common stock, preferred stock, or warrants in one or more series. Rights may be issued independently or together with any other offered security and may or may not be transferable by the person purchasing or receiving the subscription rights. In connection with any rights offering to our stockholders, we may enter into a standby underwriting arrangement with one or more underwriters pursuant to which the underwriters will purchase any of the offered securities remaining unsubscribed after the expiration of the rights offering. In connection with a rights offering to our stockholders, we will distribute certificates evidencing the rights and an applicable prospectus supplement to our stockholders on the record date that we set for receiving rights in the rights offering. An applicable prospectus supplement will describe the following terms of rights in respect of which this prospectus is being delivered:

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the title of the rights;

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the securities for which the rights are exercisable;

•

the exercise price for the rights;

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the date of determining the security holders entitled to the rights distribution;

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the number of the rights issued to each security holder;

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the extent to which the rights are transferable;

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if applicable, a discussion of the material United States federal income tax considerations applicable to the issuance or exercise of the rights;

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the date on which the right to exercise the rights shall commence, and the date on which the rights shall expire (subject to any extension);

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the conditions to completion of the rights offering;

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any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the rights;

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the extent to which the rights include an over-subscription privilege with respect to unsubscribed securities;

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if applicable, the material terms of any standby underwriting or other purchase arrangement that we may enter into in connection with the rights offering; and

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any other terms of the rights, including terms, procedures and limits relating to the exchange or exercise of the rights.

Each right will entitle the holder to purchase an amount of securities for cash, at the exercise price. Rights may be exercised at any time up to the close of business on the expiration date of the rights. After the close of business on the expiration date, all unexercised rights will become void. The manner in which rights may be exercised will be described in an applicable prospectus supplement. We may, but are not be required to, permit the exercise of rights through the delivery of a notice of guaranteed delivery from a bank, a trust company, or a Nasdaq member guaranteeing delivery of (i) payment of the exercise price for the securities for which the rights are being exercised, and (ii) a properly completed and executed rights certificate. The notice of guaranteed delivery must be received by

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the rights agent before the expiration of the rights, and the rights agent will not honor a notice of guaranteed delivery unless a properly completed and executed rights certificate and full payment for the securities being purchased are received by the rights agent by the close of business on the third business day after the expiration time of the rights. Upon receipt of payment and the proper completion and due execution of the rights certificate at the designated office of the rights agent or any other office indicated in an applicable prospectus supplement, we or the transfer agent will forward, as soon as practicable, the securities purchased upon the exercise of the rights. We may determine to offer any unsubscribed offered securities directly to persons other than stockholders, to or through agents, underwriters or dealers or through a combination of the methods, including pursuant to standby underwriting arrangements, as set forth in an applicable prospectus supplement.

DESCRIPTION OF UNITS WE MAY OFFER

The following description, together with the additional information we may include in any applicable prospectus supplements and free writing prospectuses, summarizes the material terms and provisions of the units that we may offer under this prospectus. While the terms we have summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. The terms of any units offered under a prospectus supplement may differ from the terms described below. However, no prospectus supplement will fundamentally change the terms that are set forth in this prospectus or offer a security that is not registered and described in this prospectus at the time of its effectiveness.

We will file as exhibits to the registration statement of which this prospectus is a part, or will incorporate by reference from a current report on Form 8-K that we file with the SEC, the form of unit agreement that describes the terms of the series of units we are offering, and any supplemental agreements, before the issuance of the related series of units. The following summaries of material terms and provisions of the units are subject to, and qualified in their entirety by reference to, all the provisions of the unit agreement and any supplemental agreements applicable to a particular series of units. We urge you to read the applicable prospectus supplements related to the particular series of units that we sell under this prospectus, as well as the complete unit agreement and any supplemental agreements that contain the terms of the units.

General

We may issue units comprised of one or more shares of common stock, shares of preferred stock, debt securities, warrants and/or rights in any combination. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

We will describe in the applicable prospectus supplement the terms of the series of units, including:

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the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;

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any provisions of the governing unit agreement that differ from those described below; and

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any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units.

The provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Preferred Stock,” “Description of Debt Securities,” “Description of Warrants” and “Description of Rights” will apply to each unit and to any common stock, preferred stock, debt security or warrant included in each unit, respectively.

Issuance in Series

We may issue units in such amounts and in numerous distinct series as we determine.

Enforceability of Rights by Holders of Units

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Each unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

We, the unit agents and any of their agents may treat the registered holder of any unit certificate as an absolute owner of the units evidenced by that certificate for any purpose and as the person entitled to exercise the rights attaching to the units so registered, despite any notice to the contrary.

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PLAN OF DISTRIBUTION

We may sell the securities being offered by us in this prospectus pursuant to underwritten public offerings, negotiated transactions, block trades, in transactions as further described below, any combination of such methods or any other methods permitted pursuant to applicable law. We may sell the securities to or through underwriters, dealers, agents or directly to one or more purchasers. We and our agents reserve the right to accept and to reject, in whole or in part, any proposed purchase of securities. A prospectus supplement or post-effective amendment, which we will file each time we effect an offering of any securities, will provide the names of any underwriters, dealers or agents, if any, involved in the sale of such securities, and any applicable fees, commissions, or discounts to which such persons shall be entitled to in connection with such offering.

We and our agents, dealers and underwriters, as applicable, may sell the securities being offered by us in this prospectus from time to time in one or more transactions at:

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a fixed price or prices, which may be changed;

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market prices prevailing at the time of sale;

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prices related to such prevailing market prices;

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varying prices determined at the time of sale; or

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negotiated prices.

We may determine the price or other terms of the securities offered under this prospectus by use of an electronic auction. We will describe how any auction will determine the price or any other terms, how potential investors may participate in the auction and the nature of the underwriters’ obligations, in the applicable prospectus supplement or amendment.

We may solicit directly offers to purchase securities. We may also designate agents from time to time to solicit offers to purchase securities. Any agent that we designate, who may be deemed to be an underwriter as such term is defined in the Securities Act, may then resell such securities to the public at varying prices to be determined by such agent at the time of resale.

We may engage in at the market offerings of the Company’s common stock as defined in Rule 415(a)(4) under the Securities Act. An at the market offering is an offering of our common stock at other than a fixed price, and is conducted to or through a market maker. We shall name any underwriter or agent that the Company engages for an at the market offering in a post-effective amendment to the registration statement containing this prospectus. In the related prospectus supplement, we shall also describe any additional details of the Company’s arrangement with such underwriter or agent, including commissions or fees paid or discounts offered by the Company, and whether such underwriter is acting as principal or agent.

If we use underwriters to sell securities, we will enter into an underwriting agreement with the underwriters at the time of the sale to them, which agreement shall be filed as an exhibit to the related prospectus supplement. Underwriters may also receive commissions from purchasers of the securities. Underwriters may also use dealers to sell securities. In such an event, the dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agents.

Under agreements that they may enter into with us, underwriters, dealers, agents and other persons may be entitled to (i) indemnification by the Company against certain civil liabilities, including liabilities under the Securities Act or (ii) contribution with respect to payments which they may be required to make in respect of such liabilities. Underwriters and agents may engage in transactions with, or perform services for, us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we may authorize underwriters, dealers or other persons to solicit offers by certain institutions to purchase the securities offered by us under this prospectus pursuant to contracts providing for payment and delivery on a future date or dates. The obligations of any purchaser under these contracts will be subject only to those conditions described in the applicable prospectus supplement, and the prospectus supplement will set forth the price to be paid for securities pursuant to those contracts and the commissions payable for solicitation of the contracts.

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Any underwriter may engage in over-allotment, stabilizing and syndicate short covering transactions and penalty bids in accordance with Regulation M of the Exchange Act. Over-allotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions involve bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Syndicate short covering transactions involve purchases of securities in the open market after the distribution has been completed in order to cover syndicate short positions. Penalty bids permit the underwriters to reclaim selling concessions from dealers when the securities originally sold by such dealers are purchased in covering transactions to cover syndicate short positions. These transactions may cause the price of the securities sold in an offering to be higher than it would otherwise be. These transactions, if commenced, may be discontinued by the underwriters at any time without notice.

Our common stock is quoted on The Nasdaq Capital Market under the trading symbol “SABS” The other securities are not listed on any securities exchange or other stock market and, unless the Company states otherwise in the applicable prospectus supplement, the Company does not intend to apply for listing of the other securities on any securities exchange or other stock market. Any underwriters to whom we sell securities for public offering and sale may make a market in the securities that they purchase, but the underwriters will not be obligated to do so and may discontinue any market making at any time without notice. Accordingly, the Company gives you no assurance as to the development or liquidity of any trading market for the securities.

The anticipated date of delivery of the securities offered hereby will be set forth in the applicable prospectus supplement relating to each offering.

In order to comply with certain state securities laws, if applicable, the securities may be sold in such jurisdictions only through registered or licensed brokers or dealers. In certain states, the securities may not be sold unless the securities have been registered or qualified for sale in such state or an exemption from regulation or qualification is available and is complied with. Sales of securities must also be made by the Company in compliance with all other applicable state securities laws and regulations.

We shall pay all expenses of the registration of the securities.

EXPERTS

The consolidated financial statements of SAB Biotherapeutics, Inc. as of and for the years ended December 31, 2024 and 2023, included in our Annual Report on Form 10-K for the year ended December 31, 2024, have been audited by EisnerAmper LLP, independent registered public accounting firm, as set forth in their report (which report includes an explanatory paragraph regarding the existence of substantial doubt about our ability to continue as a going concern), and have been incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

LEGAL MATTERS

If and when the securities being registered hereunder are issued, the validity of such issuance will be passed upon for the Company by Dentons US LLP, New York, New York.

WHERE YOU CAN FIND MORE INFORMATION

This prospectus is part of the registration statement on Form S-3 we filed with the SEC under the Securities Act and does not contain all the information set forth in the registration statement. Whenever a reference is made in this prospectus to any of our contracts, agreements or other documents, the reference may not be complete and you should refer to the exhibits that are a part of the registration statement or the exhibits to the reports or other documents incorporated by reference into this prospectus for a copy of such contract, agreement or other document. Because we are subject to the information and reporting requirements of the Exchange Act, we file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov.

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INFORMATION INCORPORATED BY REFERENCE

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Our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with SEC on March 31, 2025;

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Our Quarterly Reports on Form 10-Q for the fiscal periods ended March 31, 2025, June 30, 2025, and September 30, 2025, filed with the SEC on May 9, 2025, August 7, 2025, and November 14, 2025, respectively;

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Our Current Reports on Form 8-K filed with the SEC on January 28, 2025, February 5, 2025, July 17, 2025, July 21, 2025, September 26, 2025, September 30, 2025, and December 29, 2025; and

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The description of our common stock and warrants in our registration statement on Form 8-A filed with the SEC on January 8, 2021, including any amendments or reports filed for the purpose of updating such description.

You can request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

SAB Biotherapeutics, Inc.

777 W 41st St., Suite 401

Miami Beach, Florida 33140

Attn: Corporate Secretary

(305)-845-2813

* * *

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Shares of Common Stock

Pre-funded Warrants to Purchase up to Shares of Common Stock

Shares of Common Stock Underlying the Pre-funded Warrants

     PROSPECTUS SUPPLEMENT

    

Joint Bookrunning Managers

Jefferies UBS Investment Bank Citigroup Barclays

Lead Manager

Chardan

_________________________

March , 2026

ABOUT THIS PROSPECTUS SUPPLEMENT

PROSPECTUS SUPPLEMENT SUMMARY

THE OFFERING

ABOUT THIS PROSPECTUS

TRADEMARKS

PROSPECTUS SUMMARY

RISK FACTORS

USE OF PROCEEDS

PLAN OF DISTRIBUTION

EXPERTS

LEGAL MATTERS

WHERE YOU CAN FIND MORE INFORMATION

INFORMATION INCORPORATED BY REFERENCE

SEC Form 424B5 filed by SAB Biotherapeutics Inc.