Boundless Bio (BOLD) grants 220,000 stock options to officer

Rhea-AI Filing Summary

Boundless Bio, Inc. granted a stock option to Chief Legal Officer and Corporate Secretary Jessica Oien. The option covers 220,000 shares of common stock at an exercise price of $1.26 per share.

The option was awarded on January 23, 2026 and expires on January 22, 2036. Vesting starts on January 1, 2026 and occurs in 48 substantially equal monthly installments, so 1/48th of the option vests on February 1, 2026 and monthly thereafter, aligning the award with long-term service at the company.

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

OMB APPROVAL

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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^*

Oien Jessica

(Last) (First) (Middle)

C/O BOUNDLESS BIO, INC.

10955 ALEXANDRIA WAY, SUITE 100

(Street)

SAN DIEGO CA 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)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	See Remarks

3. Date of Earliest Transaction (Month/Day/Year)
01/23/2026

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)
			Code	V	Amount	(A) or (D)	Price

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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (right to buy)	$1.26	01/23/2026		A		220,000		(1)	01/22/2036	Common Stock	220,000	$0	220,000	D

Explanation of Responses:

1. The vesting commencement date is January 1, 2026. The stock option vests in 48 substantially equal monthly installments. Accordingly, 1/48th of this stock option vests on February 1, 2026, and monthly thereafter.

Remarks:

Chief Legal Officer and Corporate Secretary

	/s/ Jessica Oien	01/23/2026
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction was reported for BOLD in this Form 4?

The filing reports a grant of a stock option to an officer of Boundless Bio, Inc. covering 220,000 shares of common stock.

Who received the stock option grant at Boundless Bio (BOLD)?

The stock option was granted to Jessica Oien, who serves as Boundless Bio's Chief Legal Officer and Corporate Secretary.

How many shares are underlying the Boundless Bio (BOLD) stock option grant?

The stock option gives the right to purchase 220,000 shares of Boundless Bio, Inc. common stock.

What is the exercise price and term of the Boundless Bio (BOLD) option grant?

The option has an exercise price of $1.26 per share and an expiration date of January 22, 2036.

How does the Boundless Bio (BOLD) stock option vest for the officer?

Vesting begins on January 1, 2026 and occurs in 48 substantially equal monthly installments, with 1/48th vesting on February 1, 2026 and monthly thereafter.

Is the Boundless Bio (BOLD) option grant held directly or indirectly?

The Form 4 shows the 220,000 derivative securities as directly owned by the reporting person.