DEF 14A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No. )

Filed by the Registrant ☒

Filed by a party other than the Registrant ☐

Check the appropriate box:


☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☒	Definitive Proxy Statement
☐	Definitive Additional Materials
☐	Soliciting Material under § 240.14a-12

EQUILLIUM, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):


☒	No fee required
☐	Fee paid previously with preliminary materials
☐	Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

EQUILLIUM, INC.

2223 Avenida De La Playa, Suite 105

La Jolla, CA 92037

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

Virtual Meeting Only – No Physical Meeting Location

To Be Held On May 28, 2026

Dear Stockholder:

You are cordially invited to attend the 2026 annual meeting of stockholders (the “Annual Meeting”) of Equillium, Inc., a Delaware corporation (the “Company”). The meeting will be held on Thursday, May 28, 2026, starting at 1:00 p.m. (Pacific Time). The Annual Meeting will be a virtual meeting of stockholders, which will be conducted only via a live audio webcast. You will be able to attend the Annual Meeting, submit your questions and vote online during the meeting by visiting www.proxydocs.com/EQ. A complete list of record stockholders will be available for examination on a reasonably accessible electronic network by any stockholder for any purpose germane to the Annual Meeting for a period of ten days ending on the day before the Annual Meeting date. If you would like to view the list, please email us at ir@equilliumbio.com. The meeting will be held for the following purposes:

To elect the Board’s two nominees for Class II director named as nominees in this Proxy Statement to hold office until the 2029 Annual Meeting of Stockholders and their successors are duly elected and qualified, or until their earlier death, resignation or removal;

To approve an amendment to our Amended and Restated Certificate of Incorporation to effect a reverse stock split of our common stock at a ratio in the range of 1-for-2 to 1-for-20, inclusive, with such ratio to be determined in the discretion of our Board of Directors and with such reverse stock split to be effected at such time and date, if at all, as determined by our Board of Directors in its sole discretion;

To ratify the appointment by the Audit Committee of the Board of Crowe LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2026;

To approve an amendment to the Company's Amended and Restated Certificate of Incorporation to increase the authorized number of shares of common stock from 200,000,000 to 400,000,000 shares; and

To conduct any other business properly brought before the Annual Meeting.

These items of business are more fully described in the Proxy Statement accompanying this Notice.

The Annual Meeting will be held virtually through a live webcast. Stockholders of record at the close of business on April 1, 2026 and their proxy holders will be able to attend the Annual Meeting, submit questions and vote during the live webcast by visiting www.proxydocs.com/EQ and entering the Control Number included in your Notice of Internet Availability or in the instructions that you received via email. Please refer to the additional logistical details

and recommendations in the accompanying proxy statement. You may log in beginning at 12:45p.m. Pacific Time, on May 28, 2026.

Only stockholders of record at the close of business on April 1, 2026 and their proxy holders may vote at the meeting or any adjournment thereof.

Your vote is important. Voting your shares will ensure the presence of a quorum at the Annual Meeting and will save us the expense of further solicitation.

Important Notice Regarding the Availability of Proxy Materials for

the Annual Meeting to Be Held on May 28, 2026 starting at 1:00 p.m. (Pacific Time) at

www.proxydocs.com/EQ.

The proxy statement and annual report to stockholders are available at www.proxydocs.com/EQ.

Please promptly vote your shares by following the instructions for voting on the Notice Regarding the Availability of Proxy Materials or, if you received a paper or electronic copy of our proxy materials, by completing, signing, dating and returning your proxy card or by Internet or telephone voting as described on your proxy card.

     By Order of the Board of Directors,

    

     Bruce D. Steel
Chief Executive Officer
La Jolla, California

    

     April 15, 2026

    

You are cordially invited to attend the Annual Meeting online. Whether or not you expect to attend the Annual Meeting, please vote over the telephone or the internet as instructed in these materials, or, if you receive a paper proxy card by mail, by completing and returning the proxy mailed to you, as promptly as possible in order to ensure your representation at the Annual Meeting. Even if you have voted by proxy, you may still vote online if you attend the Annual Meeting.

EQUILLIUM, INC.

2223 Avenida De La Playa, Suite 105

La Jolla, CA 92037

PROXY STATEMENT

FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS

Virtual Meeting Only – No Physical Meeting Location

To Be Held On May 28, 2026

This proxy statement (the “Proxy Statement”) and our annual report for the fiscal year ended December 31, 2025 (the “Annual Report” and, together with this Proxy Statement, the “proxy materials”) are being furnished by and on behalf of the board of directors (the “Board” or “Board of Directors”) of Equillium, Inc. (the “Company,” “Equillium,” “we,” “us,” or “our”), in connection with our 2026 annual meeting of stockholders (the “Annual Meeting”). The Notice of Annual Meeting and this Proxy Statement are first being distributed or made available, as the case may be, on or about April 15, 2026.

iii

TABLE OF CONTENTS


	Page
SCHEDULE 14A
NOTICE OF ANNUAL MEETING OF STOCKHOLDERS
QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING	1
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	9
PROPOSAL 1: ELECTION OF DIRECTORS	10
Nominees for Election to the Board of Directors	10
Class II Director Nominees for Election at the Annual Meeting	11
Class III Directors Continuing in Office Until the 2027 Annual Meeting of Stockholders	11
Class I Directors Continuing in Office Until the 2028 Annual Meeting of Stockholders	13
INFORMATION REGARDING THE BOARD OF DIRECTORS AND CORPORATE GOVERNANCE	13
Independence of the Board of Directors	13
Board Leadership Structure	14
Role of the Board in Risk Oversight	14
Meetings of the Board of Directors	14
Executive Sessions	14
INFORMATION REGARDING COMMITTEES OF THE BOARD of Directors	15
Audit Committee	15
Compensation Committee	16
Compensation Committee Processes and Procedures	17
Nominating and Corporate Governance Committee	18
Board Diversity	20
Board’s Oversight of Strategy	20
Cybersecurity and Data Privacy Oversight	20
Stockholder Communications with The Board of Directors	21
Code of Business Conduct and Ethics	21
Insider Trading Policy	22
Hedging and Pledging Policy	22
PROPOSAL 2: APPROVAL OF AN AMENDMENT TO OUR AMENDED AND restated certificate of incorporation	23
Background	23
Approval of Reverse Stock Split of our Common Stock (Proposal 2)	23
Reasons for Reverse Stock Split	24
Criteria to be Used for Determining Whether to Implement Reverse Stock Split	24
Certain Risks and Potential Disadvantages Associated with Reverse Stock Split	24


Effects of Reverse Stock Split	25
Effective Date	27
Cash Payment In Lieu of Fractional Shares	27
Record and Beneficial Stockholders	27
Accounting Consequences	29
No Appraisal Rights	29
Material U.S. Federal Income Tax Consequences	29
Taxation of U.S. Holders	30
Information Reporting and Backup Withholding	31
PROPOSAL 3: RATIFICATION OF APPOINTMENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM	32
Principal Accountant Fees and Services	32
Pre-Approval Policies and Procedures	33
Report of the Audit Committee of the Board of Directors	34
PROPOSAL 4: Approval of amendment to OUR amended and restated certificate of incorporation to increase the AUTHORIZED number of shares of common stock	35
EXECUTIVE OFFICERS	36
EXECUTIVE AND DIRECTOR COMPENSATION	37
Executive Summary	37
Summary Compensation Table	40
Compensation Program Overview	40
Annual Base Salary	40
Non-Equity Incentive Plan Compensation	41
Equity-Based Incentive Awards	42
Agreements with our Named Executive Officers	43
Potential Payments and Benefits upon Termination or Change in Control	43
Outstanding Equity Awards at Fiscal Year-End	44
Option Repricings	45
Perquisites Health, Welfare and Retirement Benefits	45
401(k) Plan	45
Nonqualified Deferred Compensation	45
Securities Authorized for Issuance under Equity Compensation Plans	46
Clawbacks	46
Equity Benefit Plans	46
2018 Equity Incentive Plan	46
2017 Equity Incentive Plan	48
2024 Inducement Plan	49


2018 Employee Stock Purchase Plan	50
Director Compensation	50
Non-Employee Director Compensation Policy	51
Item 402(v) Pay Versus Performance	52
Required Tabular Disclosure of Pay Versus Performance	52
Required Disclosure of the Relationship Between CAP and Financial Performance Measures	54
Policies and Practices Related to the Grant of Certain Equity Awards Close in Time to the Release of Material Nonpublic Information	56
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT	57
TRANSACTIONS WITH RELATED PERSONS AND INDEMNIFICATION	60
Related-Person Transactions Policy and Procedures	60
Certain Related-Person Transactions	60
Employment Arrangements	60
Stock Options Granted to Executive Officers and Directors	60
Biocon Agreements	61
Ariagen Acquisition	61
Indemnification Agreements	62
OTHER INFORMATION FOR STOCKHOLDERS	63
Stockholder Proposals for the 2026 Annual Meeting of Stockholders	63
HOUSEHOLDING OF PROXY MATERIALS	64
ADDITIONAL FILINGS	64
OTHER MATTERS	65
APPENDIX A	66
APPENDIX B	68

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why did I receive a notice in the mail regarding the Internet availability of proxy materials instead of a paper copy of proxy materials?

Pursuant to rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our proxy materials over the internet. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials (the “Notice”) because the Board of the Company is soliciting your proxy to vote at the 2026 Annual Meeting of Stockholders, including at any adjournments or postponements of the meeting. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the internet or to request a printed copy may be found in the Notice.

We intend to first mail the Notice and make this Proxy Statement and the form of proxy available to stockholders on or about April 15, 2026.

Will I receive any other proxy materials by mail?

We may send you a proxy card, along with a second Notice, on or after April 25, 2026.

How do I attend the Annual Meeting?

This year’s Annual Meeting will be a virtual meeting, which will be conducted entirely online via webcast to allow greater participation. You may attend, vote and ask questions at the Annual Meeting by following the instructions provided on the Notice or proxy card to log in to www.proxydocs.com/EQ. If you are a stockholder of record, you will be asked to provide the control number from your Notice or proxy card. If you are a beneficial owner of shares registered in the name of your broker, bank or other agent, follow the instructions from your broker or bank.

The webcast of the Annual Meeting will begin promptly at 1:00 p.m. Pacific Time. We encourage you to access the meeting prior to the start time. Online check-in will begin at 12:45 p.m. Pacific Time, and you should allow reasonable time for the check-in procedures.

You are entitled to attend the Annual Meeting if you were a stockholder as of the close of business on April 1, 2026, the record date, or hold a valid proxy for the meeting. To be admitted to the Annual Meeting, you will need to visit www.proxydocs.com/EQ and enter the Control Number found next to the label “Control Number” on your Notice or proxy card, or in the email sending you the Proxy Statement. If you are a beneficial stockholder, you should contact the bank, broker or other institution where you hold your account well in advance of the meeting if you have questions about obtaining your control number/proxy to vote.

Whether or not you participate in the Annual Meeting, it is important that you vote your shares.

What if I cannot find my Control Number?

Please note that if you do not have your Control Number and you are a registered stockholder, you will be able to login as a guest. To view the meeting webcast visit www.proxydocs.com/EQ and register as a guest. If you login as a guest, you will not be able to vote your shares or ask questions during the meeting.

If you are a beneficial owner (that is, you hold your shares in an account at a bank, broker or other holder of record), you will need to contact that bank, broker or other holder of record to obtain your Control Number prior to the Annual Meeting.

Where can we get technical assistance if we are having trouble accessing the meeting or during the meeting?

If you have difficulty accessing the meeting or during the meeting, please refer to the technical support telephone number posted on the virtual meeting website login page, where technicians will be available to help you.

For the Annual Meeting, how do we ask questions of management and the Board?

Stockholders may submit questions relevant to the proposals to be voted on at the Annual Meeting for approximately five days in advance of the Annual Meeting through www.proxydocs.com/EQ. We plan to spend up to 15 minutes answering appropriate stockholder questions after the proposals are formally presented and prior to the closing of voting at the Annual Meeting and will include as many stockholder questions that comply with the rules of conduct for the Annual Meeting as the allotted time permits. If we receive substantially similar questions, we will group such questions together and provide a single response to avoid repetition. Questions that are not relevant to the proposals to be voted on at the Annual Meeting and not in compliance with the rules of conduct for the Annual Meeting will not be responded to. Questions may be submitted during the Annual Meeting through www.proxydocs.com/EQ.

Who can vote at the Annual Meeting?

Only stockholders of record at the close of business on April 1, 2026 will be entitled to vote at the Annual Meeting. On this record date, there were 63,226,556 shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

If, on April 1, 2026, your shares were registered directly in your name with our transfer agent, Equiniti Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you may vote online during the Annual Meeting or vote by proxy. Whether or not you plan to register and attend the Annual Meeting, we urge you to fill out and return your vote by proxy over the telephone, vote by proxy through the internet or voting by proxy using a proxy card that you may request or that we may elect to deliver at a later time to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker or Bank

If on April 1, 2026, your shares were held, not in your name, but rather in an account at a brokerage firm, bank or other similar organization, then you are the beneficial owner of shares held in “street name” and the Notice should be forwarded to you by that organization. The organization holding your account is considered to be the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker, bank or other agent regarding how to vote the shares in your account. You must follow the instructions provided by your brokerage firm, bank, or other similar organization for your bank, broker or other stockholder of record to vote your shares per your instructions. Alternatively, many brokers and banks provide the means to grant proxies or otherwise instruct them to vote your shares by telephone and via the Internet, including by providing you with a control number via email or on your Notice or your voting instruction form. If your shares are held in an account with a broker, bank or other stockholder of record providing such a service, you may instruct them to vote your shares by telephone (by calling the number provided in the proxy materials) or over the Internet as instructed by your broker, bank or other stockholder of record. If you did not receive a control number via email or on your Notice or voting instruction form, and you wish to vote prior to or at the virtual Annual Meeting, you must follow the instructions from your broker, bank or other stockholder of record, including any requirement to obtain a valid legal proxy. Many brokers, banks and other stockholders of record allow a beneficial owner to obtain a valid legal proxy either online or by mail, and we recommend that you contact your broker, bank or other stockholder of record to do so.

Can I vote my shares by filling out and returning the Notice?

No. The Notice identifies the items to be voted on at the Annual Meeting, but you cannot vote by marking the Notice and returning it. If you would like a paper proxy card, you should follow the instructions in the Notice. The paper proxy card you may receive would also provide instructions as to how to authorize via the Internet or telephone your proxy to vote your shares according to your voting instructions. Alternatively, you can mark the paper proxy card you may receive with how you would like your shares voted, sign and date the proxy card, and return it in the envelope provided.

Will a list of record stockholders as of the record date be available?

For the ten days ending the day prior to the Annual Meeting, a list of our record stockholders as of the close of business on the record date will be available for examination by any stockholder of record for a legally valid purpose at our corporate headquarters during regular business hours. To access the list of record stockholders beginning May 18, 2026 and until the day prior to the Annual Meeting, stockholders should email ir@equilliumbio.com.

What am I voting on?

There are four matters scheduled for a vote:

•

Proposal 1: To elect the Board’s two nominees for Class II director named as nominees in this Proxy Statement to serve until the 2029 Annual Meeting of Stockholders and their successors are duly elected and qualified, or until their earlier death, resignation or removal;

•

Proposal 2: Approval of an amendment to our Amended and Restated Certificate of Incorporation to effect a reverse stock split of our common stock at a ratio in the range of 1-for-2 to 1-for-20, inclusive, with such ratio to be determined in the discretion of our Board of Directors and with such reverse stock split to be effected at such time and date, if at all, as determined by our Board of Directors in its sole discretion;

•

Proposal 3: To ratify the appointment by the Audit Committee of the Board of Crowe LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2026; and

•

Proposal 4: To approve an amendment to our Amended and Restated Certificate of Incorporation to increase the authorized number of shares of common stock from 200,000,000 to 400,000,000 shares.

What if another matter is properly brought before the Annual Meeting?

The Board does not know of any other matters to be brought before the Annual Meeting. If other matters are presented, the proxy holders have discretionary authority to vote all proxies in accordance with their best judgment. Discretionary authority for them to do so is provided in the proxy card.

How do I vote?

For Proposal 1, you may either vote “For” all the nominees to the Board or you may “Withhold” your vote for any nominee to the Board that you specify. For each of the other matters to be voted on, you may vote “For” or “Against” or abstain from voting.

The procedures for voting are as follows:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote at the Annual Meeting or you may vote by proxy over the telephone, through the internet or using a proxy card that you may request or that we may elect to deliver at a later time. Whether or not you plan to attend the Annual Meeting, we urge you to vote by proxy to ensure your vote is

counted. You may still attend the Annual Meeting and vote at the Annual Meeting even if you have already voted by proxy. This is only required if you want to change your original vote, since votes will not be double counted.

•

VOTE DURING THE ANNUAL MEETING: To vote during the live webcast of the Annual Meeting, you must first register at www.proxydocs.com/EQ. Upon completing your registration, you will receive further instructions via email, including your unique link that will allow you access to the Annual Meeting and to submit questions during the meeting. Please be sure to follow instructions found on www.proxydocs.com/EQ or your proxy card and subsequent instructions that will be delivered to you via email. Stockholders will be able to attend the Annual Meeting platform beginning at 12:45 p.m. (Pacific Time) on May 28, 2026, pursuant to the unique access instructions they receive following their registration at www.proxydocs.com/EQ.

•

TO VOTE BY PHONE: To vote over the telephone, dial toll-free 855-680-7102 using any touch-tone telephone and follow the recorded instructions. You will be asked to provide the control number from your Notice. Your telephone vote must be received by 1:00 p.m. Pacific Time on May 28, 2026 to be counted.

•

TO VOTE BY INTERNET: You can vote over the Internet at www.proxypush.com/EQ by following the instructions on the Notice or proxy card that may be delivered to you. Your internet vote must be received by 1:00 p.m. Pacific Time on May 28, 2026 to be counted.

•

TO VOTE BY PROXY CARD: To vote using the proxy card, simply complete, sign and date the proxy card that may be delivered to you and return it promptly in the envelope we have provided or return it to: Proxy Tabulator for Equillium, Inc., P.O. Box 8016, Cary, North Carolina 27512-9903. If you return your signed proxy card to us before the Annual Meeting, we will vote your shares as you direct.

Beneficial Owner: Shares Registered in the Name of Broker or Bank

If you are a beneficial owner of shares registered in the name of your brokerage firm, bank or other agent, you should have received a voting instruction form with the Notice from that organization rather than from Equillium. Simply complete and mail the voting instruction form to ensure that your vote is counted. Alternatively, you may vote by telephone or over the internet as instructed by your broker, bank or other agent. To vote at the Annual Meeting, you must register at www.proxydocs.com/EQ prior to the deadline of May 27, 2026 at 2:00 p.m. (Pacific Time). You may be instructed to obtain a legal proxy from your broker, bank or other nominee and to submit a copy in advance of the Annual Meeting. Further instruction will be provided to you as part of your registration process.

Internet proxy voting will be provided to allow you to vote your shares online, with procedures designed to ensure the authenticity and correctness of your proxy vote instructions. However, please be aware that you must bear any costs associated with your internet access, such as usage charges from internet access providers and telephone companies.

How many votes do I have?

On each matter to be voted upon, you have one vote for each share of common stock you own as of the close of business on April 1, 2026.

If I am a stockholder of record and I do not vote, or if I return a proxy card or otherwise vote without giving specific voting instructions, what happens?

If you are a stockholder of record and do not vote by completing your proxy card, by telephone, through the internet or online at the Annual Meeting, your shares will not be voted.

If you return a signed and dated proxy card or otherwise vote without marking voting selections, your shares will be voted, as applicable, “For” the election of both nominees for director, “For” the approval of an amendment to our Amended and Restated Certificate of Incorporation to effect a reverse stock split of our common stock at a ratio in the range of 1-for-2 to 1-for-20, inclusive, “For” the ratification of the appointment by the Audit Committee of the Board of Crowe LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026 and

“For” the approval of an increase in authorized shares. If any other matter is properly presented at the meeting, your proxy holder (one of the individuals named on your proxy card) will vote your shares using that individual’s best judgment.

If I am a beneficial owner of shares held in street name and I do not provide my broker or bank with voting instructions, what happens?

If you are a beneficial owner of shares held in street name and you do not instruct your broker, bank or other agent how to vote your shares, your broker, bank or other agent may still be able to vote your shares in its discretion. Brokers, banks and other securities intermediaries may use their discretion to vote your “uninstructed” shares with respect to matters considered to be “routine,” but not with respect to “non-routine” matters. In this regard, Proposal 1 is considered to be “non-routine,” meaning that your broker may not vote your shares on these proposals in the absence of your voting instructions. Proposals 2, 3 and 4 are each considered to be “routine,” meaning that if you do not return voting instructions to your broker by its deadline, your shares may be voted by your broker in its discretion on Proposals 2, 3 and 4.

What are “broker non-votes”?

As discussed above, when a beneficial owner of shares held in street name does not give voting instructions to his or her broker, bank or other securities intermediary holding his or her shares as to how to vote on matters deemed to be “non-routine,” the broker, bank or other such agent cannot vote the shares. When there is at least one “routine” matter that the broker, bank or other securities intermediary votes on, the shares that are un-voted on “non-routine” matters are counted as “broker non-votes.” Proposals 2, 3 and 4 are each considered to be a “routine” matter and we therefore expect brokers, banks or other securities intermediaries to vote on such proposals. Proposal 1 is considered to be “non-routine” and we therefore expect broker non-votes to exist in connection with such proposal.

As a reminder, if you are a beneficial owner of shares held in street name, in order to ensure your shares are voted in the way you would prefer, you must provide voting instructions to your broker, bank or other agent by the deadline provided in the materials you receive from your broker, bank or other agent.

Who is paying for this proxy solicitation?

Equillium will pay for the entire cost of soliciting proxies. In addition to these proxy materials, our directors and employees may also solicit proxies in person, by email, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. We may also reimburse brokerage firms, banks or other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one Notice or more than one set of proxy materials?

If you receive more than one Notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the Notices to ensure that all of your shares are voted.

Can I change my vote after submitting my proxy?

Stockholder of Record: Shares Registered in Your Name

Yes. You can revoke your proxy at any time before the final vote at the Annual Meeting. If you are the record holder of your shares, you may revoke your proxy in any one of the following ways:

•

You may submit another properly completed proxy card with a later date.

•

You may grant a subsequent proxy by telephone or through the internet.

•

You may send a timely written notice that you are revoking your proxy to Equillium’s Secretary at 2223 Avenida de la Playa, Suite 105, La Jolla, CA 92037, provided that such notice is received no later than May 27, 2026.

•

You may attend the Annual Meeting and vote online. Simply attending the Annual Meeting will not, by itself, revoke your proxy.

Your most recent proxy card or telephone or internet proxy is the one that is counted.

Beneficial Owner: Shares Registered in the Name of Broker or Bank

If your shares are held by your brokerage firm, bank or other agent, you should follow the instructions provided by your broker, bank or other agent.

What vote is required for adoption or approval of each proposal and how will votes be counted?

     Proposal
Number

     Proposal
Description

     Vote Required for
 Approval

     Voting
Options

     Effect of
Abstentions
or
Withhold
Votes, as
applicable

     Effect of
Broker Non- 
Votes

     Board 
Recommendation

     1

     Election of Directors named in this Proxy Statement

     The nominees receiving the most “For” votes will be elected.

     FOR or WITHHOLD

     No Effect

     No Effect

     FOR both nominees

     2

     Approval of an amendment to our Amended and Restated Certificate of Incorporation to effect a reverse stock split of our common stock at a ratio in the range of 1-for-2 to 1-for- 20, inclusive, with such ratio to be determined in the discretion of our Board of Directors and with such reverse stock split to be effected at such time and date, if at all, as determined by our Board of Directors in its sole discretion

     “For” votes from a majority of the votes cast on this proposal is required for approval.

     FOR, AGAINST or ABSTAIN

     No Effect

     No Effect

     FOR

     Proposal
Number

     Proposal
Description

     Vote Required for
 Approval

     Voting
Options

     Effect of
Abstentions
or
Withhold
Votes, as
applicable

     Effect of
Broker Non- 
Votes

     Board 
Recommendation

     3

     Ratification of the appointment of Crowe LLP as the Company’s independent registered public accounting firm for the fiscal year ending 2026

     “For” votes from a majority of the shares present virtually or represented by proxy and entitled to vote on the matter is required for approval.

     FOR, AGAINST or ABSTAIN

     Against

     No Effect

     FOR

     4

     Amend Company's Amended and Restated Certificate of Incorporation to increase authorized shares of common stock from 200,000,000 to 400,000,000

     “For” votes from a majority of the votes cast on this proposal is required for approval.

     FOR, AGAINST or ABSTAIN

     No
Effect

     No Effect

     FOR

Who will count the vote?

A representative of Equillium will tabulate the votes and act as inspector of elections.

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if stockholders holding a majority of the outstanding shares entitled to vote are present at the Annual Meeting or represented by proxy. On the record date, there were 63,226,556 shares of common stock outstanding and entitled to vote. Thus, the holders of 31,613,279 shares must be present or represented by proxy at the Annual Meeting to have a quorum.

Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your brokerage firm, bank or other agent) or if you vote at the Annual Meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, the holders of a majority of shares present virtually at the Annual Meeting or represented by proxy may adjourn the Annual Meeting to another date.

How can I find out the results of the voting at the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. In addition, final voting results will be published in a current report on Form 8-K that we expect to file with the SEC within four business days after the Annual Meeting. If final voting results are not available to us in time to file a Form 8-K within four business days after the Annual Meeting, we intend to file a Form 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additional Form 8-K to publish the final results.

What proxy materials are available on the Internet?

The proxy statement and annual report to stockholders are available at www.proxydocs.com/EQ.

Why hold a virtual meeting?

We are excited to continue using the latest technology to provide expanded access, improved communication and cost savings for our stockholders and the Company while providing stockholders the same rights and opportunities to participate as they would have at an in-person meeting. We believe that hosting a virtual meeting is in the best interests of the Company and its stockholders and a virtual meeting enables increased stockholder attendance and participation because stockholders can participate from any location around the world.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Proxy Statement contains certain “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, relating to future events. Such statements are only predictions and involve risks and uncertainties, resulting in the possibility that the actual events or performance will differ materially from such predictions. For a nonexclusive list of major factors which could cause the actua

SEC Form DEF 14A filed by Equillium Inc.