Boundless Bio, Inc. Common Stock (BOLD) Form 3 Initial statement of insider ownership

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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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1. Name and Address of Reporting Person^*

Wellington Biomedical Innovation Master Investors (Cayman) I L.P.

(Last) (First) (Middle)

C/O WELLINGTON MANAGEMENT COMPANY LLP

280 CONGRESS STREET

(Street)

BOSTON MA 02210

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
03/27/2024

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

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

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

5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series B Preferred Stock	(1)	(1)	Common Stock	189,933	(1)	D
Series C Preferred Stock	(2)	(2)	Common Stock	366,300	(2)	D

Explanation of Responses:

1. Each share of Series B Preferred Stock is convertible into shares of Common Stock, on a 19.5-for-1 basis, into the number of shares of Common Stock shown in column 3 without payment of further consideration at any time at the holder's election and will convert immediately prior to the closing of the Issuer's initial public offering. The shares have no expiration date.

2. Each share of Series C Preferred Stock is convertible into shares of Common Stock, on a 19.5-for-1 basis, into the number of shares of Common Stock shown in column 3 without payment of further consideration at any time at the holder's election and will convert immediately prior to the closing of the Issuer's initial public offering. The shares have no expiration date.

	Wellington Biomedical Innovation Master Investors (Cayman) II L.P. By: Wellington Management Company LLP, as Investment Adviser /s/ Peter McIsaac, Title: Authorized Person	03/27/2024
	** 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 5 (b)(v).
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