Exhibit 5.1
OPINION OF LATHAM & WATKINS LLP
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March 28, 2024
Boundless Bio, Inc.
9880 Campus Point Drive
Suite 120
San Diego, CA 92121
| Re: | Registration Statement on Form S-8; 9,457,911 shares of Common Stock, par value $0.0001 per share |
To the addressees set forth above:
We have acted as special counsel to Boundless Bio, Inc., a Delaware corporation (the “Company”), in connection with the proposed issuance of an aggregate of 9,457,911 shares of common stock, $0.0001 par value per share (the “Shares”), of the Company, pursuant to the Company’s 2024 Incentive Award Plan (the “2024 Plan”), the Company’s 2018 Equity Incentive Plan, as amended (the “2018 Plan”), and the Company’s 2024 Employee Stock Purchase Plan (the “ESPP,” and together with the 2024 Plan and the 2018 Plan, the “Plans”). The Shares are included in a Registration Statement on Form S-8 under the Securities Act of 1933, as amended (the “Act”), filed with the Securities and Exchange Commission (the “Commission”) on March 28, 2024 (the “Registration Statement”). This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or related prospectuses, other than as expressly stated herein with respect to the issuance of the Shares.
As such counsel, we have examined such matters of fact and questions of law as we have considered appropriate for purposes of this letter. With your consent, we have relied upon certificates and other assurances of officers of the Company and others as to factual matters without having independently verified such factual matters. We are opining herein as to the General Corporation Law of the State of Delaware and we express no opinion with respect to any other laws.
In our examination, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals and the conformity to authentic original documents of all documents submitted to us as copies.