SEC FORM 4

SEC FORM 4 SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Hornby Zachary

(Last)

(First)

(Middle)

C/O BOUNDLESS BIO, INC.

9880 CAMPUS POINT DRIVE, SUITE 120

(Street)

SAN DIEGO

92121

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
Boundless Bio, Inc. [ BOLD ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	President & CEO

3. Date of Earliest Transaction (Month/Day/Year)
08/19/2024

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Stock Option	$4.1	08/19/2024		D			256,410	⁽¹⁾	06/06/2031	Common Stock	256,410	⁽²⁾	0	D
Stock Option	$4.1	08/19/2024		D			471,282	⁽³⁾	06/12/2033	Common Stock	471,282	⁽²⁾	0	D
Stock Option	$8.19	08/19/2024		D			257,207	⁽⁴⁾	02/14/2034	Common Stock	257,207	⁽²⁾	0	D
Stock Option	$16	08/19/2024		D			162,343	⁽⁵⁾	03/26/2034	Common Stock	162,343	⁽²⁾	0	D
Stock Option	$3.56⁽⁶⁾	08/19/2024		A		256,410		⁽¹⁾	06/06/2031	Common Stock	256,410	⁽²⁾	256,410	D
Stock Option	$3.56⁽⁶⁾	08/19/2024		A		471,282		⁽³⁾	06/12/2033	Common Stock	471,282	⁽²⁾	471,282	D
Stock Option	$3.56⁽⁶⁾	08/19/2024		A		257,207		⁽⁴⁾	02/14/2034	Common Stock	257,207	⁽²⁾	257,207	D
Stock Option	$3.56⁽⁶⁾	08/19/2024		A		162,343		⁽⁵⁾	03/26/2034	Common Stock	162,343	⁽²⁾	162,343	D

Explanation of Responses:

1. The stock option vests in 48 substantially equal monthly installments beginning on July 7, 2021.

2. On August 19, 2024, the Issuer repriced the option. Except as described further in footnote 6, all other terms of the option remain unchanged.

3. The stock option vests in 48 substantially equal monthly installments beginning on July 13, 2023.

4. The stock option vests in 48 substantially equal monthly installments beginning on March 15, 2024.

5. The stock option vests in 48 substantially equal monthly installments beginning on April 27, 2024.

6. The exercise price of the option is $3.56 per share, representing the fair market value per share of the common stock on the date of the repricing; provided that the exercise price will be increased to the original exercise price before repricing if, prior to the "premium end date" (as defined below), the repriced option is exercised or the reporting person's employment is terminated for any reason other than a "qualifying termination" (as defined below). The "premium end date" means the earliest of: (i) August 19, 2026, (ii) the date immediately prior to the closing of a change in control, or (iii) the date of the employee's qualifying termination. A "qualifying termination" means (a) the involuntary termination of the employee's employment by the Company due to a reduction in force (and other than for cause), or (b) the employee's termination due to death or disability.

	/s/ Jessica Oien, Attorney-in-Fact for Zachary Hornby	08/20/2024
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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SEC Form 4 filed by President & CEO Hornby Zachary