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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on March&nbsp;28, 2024 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-&#8195;&#8195;&#8195;&#8195;</FONT> </B></P>
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<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM <FONT
STYLE="white-space:nowrap">S-8</FONT> </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>BOUNDLESS BIO, INC. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B><FONT STYLE="white-space:nowrap">83-0751369</FONT></B></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or Other Jurisdiction</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>of Incorporation or Organization)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>9880 Campus Point Drive, Suite 120 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, CA 92121 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(858) <FONT STYLE="white-space:nowrap">766-9912</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of Principal Executive Offices) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boundless
Bio, Inc. 2018 Equity Incentive Plan </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boundless Bio, Inc. 2024 Incentive Award Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boundless Bio, Inc. 2024 Employee Stock Purchase Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full Title of the Plans) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Zachary
Hornby </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>President and Chief Executive Officer </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boundless Bio, Inc. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>9880
Campus Point Drive, Suite 120 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, CA 92121 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(858) <FONT STYLE="white-space:nowrap">766-9912</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name, Address and Telephone Number, Including Area Code, of Agent for Service) </B></P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>Copies to: </I></B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Cheston J. Larson </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Matthew T. Bush </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Latham&nbsp;&amp; Watkins LLP </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>12670 High Bluff Drive </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, CA 92130 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(858) <FONT STYLE="white-space:nowrap">523-5400</FONT> </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Indicate by
check mark whether the registrant is a large accelerated filer, an accelerated filer, a <FONT STYLE="white-space:nowrap">non-accelerated</FONT> filer, a smaller reporting company or an emerging growth company. See the definitions of &#147;large
accelerated filer,&#148; &#147;accelerated filer,&#148; &#147;smaller reporting company&#148; and &#147;emerging growth company&#148; in Rule <FONT STYLE="white-space:nowrap">12b-2</FONT> of the Exchange Act. </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9744;</TD></TR>
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<TD HEIGHT="8" COLSPAN="2"></TD>
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<TD VALIGN="bottom">Non-accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9746;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9746;</TD></TR>
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<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Emerging&nbsp;growth&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&#9746;</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended
transition period for complying with any new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&#8194;&#9744; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>Proposed sales to take place as soon after the effective date of the registration statement as awards granted under the above-named plans
are granted, exercised and/or distributed. </B></P> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P>
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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART I </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The documents containing the information specified in Part&nbsp;I of Form <FONT STYLE="white-space:nowrap">S-8</FONT> will be sent or given to
participants as specified by Rule&nbsp;428(b)(1) of the Securities Act. These documents and the documents incorporated by reference into this registration statement pursuant to Item&nbsp;3 of Part&nbsp;II of this registration statement, taken
together, constitute a prospectus that meets the requirements of Section&nbsp;10(a) of the Securities Act. </P> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><I>In this registration statement, Boundless Bio, Inc. is sometimes referred to as &#147;Registrant,&#148; &#147;we,&#148; &#147;us&#148; or
&#147;our.&#148; </I></P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;3. Incorporation of Documents by Reference. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Securities and Exchange Commission (&#147;SEC&#148;) allows us to &#147;incorporate by reference&#148; the information we file with them,
which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this registration statement, and later information filed with the SEC will
update and supersede this information. We hereby incorporate by reference into this registration statement the following documents previously filed with the SEC: </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">(a)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">The prospectus filed by the Registrant with the SEC pursuant to <A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524080798/d493037d424b4.htm">Rule
 424(b)</A> under the Securities Act, on March&nbsp;28, 2024 relating to the registration statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> as amended (Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-277696),</FONT> which
contains the Registrant&#146;s audited financial statements for the latest fiscal year for which such statements have been filed; and </P></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">(b)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">The description of the Registrant&#146;s common stock set forth in the Registrant&#146;s registration statement
on <A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524075413/d85831d8a12b.htm"><FONT STYLE="white-space:nowrap">Form&nbsp;8-A12B</FONT></A> (Registration No.&nbsp;001-41989), filed by the Registrant with the SEC under
Section&nbsp;12(b) of the Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), on March&nbsp;22, 2024, including any amendments or reports filed for the purpose of updating such description. </P></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">In addition, all documents filed by the Registrant pursuant to Section&nbsp;13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the
filing of this registration statement and prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which <FONT STYLE="white-space:nowrap">de-registers</FONT> all securities then remaining
unsold shall be deemed to be incorporated by reference into this registration statement and to be a part hereof from the date of filing such documents, except as to specific sections of such statements as set forth therein. Any statement contained
in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained herein or in any other subsequently filed
document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement contained herein shall be deemed to be modified or superseded for purposes of this registration statement to
the extent that a statement contained in any subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be
deemed, except as so modified or superseded, to constitute a part of this registration statement. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Under no circumstances shall any
information furnished under Item 2.02 or 7.01 of Form <FONT STYLE="white-space:nowrap">8-K</FONT> be deemed incorporated herein by reference unless such Form <FONT STYLE="white-space:nowrap">8-K</FONT> expressly provides to the contrary. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;4. Description of Securities. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;5. Interests of
Named Experts and Counsel. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;6. Indemnification of Directors and Officers. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Section 102 of the General Corporation Law of the State of Delaware permits a corporation to eliminate the personal liability of directors of a
corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly
violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Our certificate of incorporation provides that no director of the Registrant shall
be personally liable to it or its stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability, except to the extent that the General Corporation Law of the State of
Delaware prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Section&nbsp;145 of the
General Corporation Law of the State of Delaware provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation, or a person serving at the request of the corporation for another corporation,
partnership, joint venture, trust or other enterprise in related capacities against expenses (including attorneys&#146; fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with an
action, suit or proceeding to which he was or is a party or is threatened to be made a party to any threatened, ending or completed action, suit or proceeding by reason of such position, if such person acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful, except that, in the case of actions brought by or in the
right of the corporation, no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or other
adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other
court shall deem proper. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Our amended and restated certificate of incorporation and our amended and restated bylaws provide that we will
indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or proceeding (other than an action by or in the right of us) by reason of the fact that he or she is or was, or has
agreed to become, a director or officer, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or
other enterprise (all such persons being referred to as an &#147;Indemnitee&#148;), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys&#146; fees), judgments, fines and
amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding and any appeal therefrom, if such Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed
to, our best interests, and, with respect to any criminal action or proceeding, he or she had no reasonable cause to believe his or her conduct was unlawful. Our amended and restated certificate of incorporation and our amended and restated bylaws,
each as currently in effect, provide that we will indemnify any Indemnitee who was or is a party to an action or suit by or in the right of us to procure a judgment in our favor by reason of the fact that the Indemnitee is or was, or has agreed to
become, a director or officer, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other
enterprise, or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys&#146; fees) and, to the extent permitted by law, amounts paid in settlement actually and reasonably incurred in
connection with such action, suit or </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">3 </P>

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<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
proceeding, and any appeal therefrom, if the Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, our best interests, except that no
indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to us, unless a court determines that, despite such adjudication but in view of all of the circumstances, he or
she is entitled to indemnification of such expenses. Notwithstanding the foregoing, to the extent that any Indemnitee has been successful, on the merits or otherwise, he or she will be indemnified by us against all expenses (including
attorneys&#146; fees) actually and reasonably incurred in connection therewith. Expenses must be advanced to an Indemnitee under certain circumstances. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We have entered into indemnification agreements with each of our directors and officers. These indemnification agreements may require us,
among other things, to indemnify our directors and officers for some expenses, including attorneys&#146; fees, judgments, fines and settlement amounts incurred by a director or officer in any action or proceeding arising out of his or her service as
one of our directors or officers, or any of our subsidiaries or any other company or enterprise to which the person provides services at our request. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We maintain a general liability insurance policy that covers certain liabilities of directors and officers of our corporation arising out of
claims based on acts or omissions in their capacities as directors or officers. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;7. Exemption from Registration Claimed. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Not applicable. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;8. Exhibits.
</B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="52%"></TD>

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<TD VALIGN="bottom" ROWSPAN="2" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; display:table-cell; font-size:8pt; font-family:Times New Roman; "><B>Number</B></P></TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman"><B>Exhibit Description</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="14" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Incorporated by Reference</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ROWSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Filed</B><br><B>Herewith</B></TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:9pt">
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Form</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>File No.</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Exhibit</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Filing&nbsp;Date</B></TD>
<TD VALIGN="bottom">&nbsp;</TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;3.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524073230/d493037dex33.htm">Form of Amended and Restated Certificate of Incorporation </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right"><FONT STYLE="white-space:nowrap">S-1/A</FONT></TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="bottom" ALIGN="right">333&#151;&nbsp;277696</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">3.3</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">March&nbsp;21,&nbsp;2024</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;3.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524073230/d493037dex34.htm">Form of Amended and Restated Bylaws</A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right"><FONT STYLE="white-space:nowrap">S-1/A</FONT></TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="bottom" ALIGN="right">333&#151; 277696</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">3.4</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">March&nbsp;21, 2024</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524073230/d493037dex41.htm">Specimen stock certificate evidencing the shares of common stock</A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right"><FONT STYLE="white-space:nowrap">S-1/A</FONT></TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="bottom" ALIGN="right">333&#151; 277696</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">4.1</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">March&nbsp;21, 2024</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&#8199;5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dex51.htm">Opinion of Latham&nbsp;&amp; Watkins LLP </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>10.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1782303/000119312524060708/d493037dex101.htm">Boundless Bio, Inc. 2018 Equity Incentive Plan, as amended, and form of stock option agreement and form of restricted stock agreement thereunder
 </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right"><FONT STYLE="white-space:nowrap">S-1</FONT></TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD NOWRAP VALIGN="bottom" ALIGN="right">333&#151; 277696</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">10.1</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">March&nbsp;6,&nbsp;2024</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>10.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dex102.htm">Boundless Bio, Inc. 2024 Incentive Award Plan and form of stock option agreement and form of restricted stock unit agreement thereunder </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>10.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dex103.htm">Boundless Bio, Inc. 2024 Employee Stock Purchase Plan </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dex231.htm">Consent of Independent Registered Public Accounting Firm </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dex51.htm">Consent of Latham&nbsp;&amp; Watkins LLP (included in Exhibit&nbsp;5.1) </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781ds8.htm#sig">Power of Attorney (see signature page) </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD>
<TD HEIGHT="8" COLSPAN="4"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>107</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d60781dexfilingfees.htm">Calculation of Filing Fee Table </A></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="right">X</TD>
<TD NOWRAP VALIGN="bottom">&nbsp;</TD></TR>
</TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">4 </P>

</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
<HR SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&#8201;9. Undertakings. </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(a) The undersigned Registrant hereby undertakes: </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:9%; font-size:10pt; font-family:Times New Roman">(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement, </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(i) to include any prospectus required by Section&nbsp;10(a)(3) of the Securities Act; </P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(ii) to reflect in the prospectus any facts or events arising after the effective date of this registration statement (or the
most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with
the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the &#147;Calculation of Filing Fee Tables&#148; table in the effective
registration statement; and </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; margin-left:9%; text-indent:4%; font-size:10pt; font-family:Times New Roman">(iii) to include any material information with respect to the plan of distribution not
previously disclosed in this registration statement or any material change to such information in this registration statement; </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><I>provided, however</I>,
that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if this registration statement is on Form <FONT STYLE="white-space:nowrap">S-8</FONT> and the information required to be included in a post-effective amendment by those paragraphs is contained in
reports filed with or furnished to the SEC by the Registrant pursuant to Section&nbsp;13 or Section&nbsp;15(d) of the Exchange Act that are incorporated by reference in this registration statement. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:9%; font-size:10pt; font-family:Times New Roman">(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a
new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:9%; font-size:10pt; font-family:Times New Roman">(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the
termination of the offering. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the
Securities Act, each filing of the Registrant&#146;s annual report pursuant to Section&nbsp;13(a) or Section&nbsp;15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan&#146;s annual report pursuant to
Section&nbsp;15(d) of the Exchange Act) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement, relating to the securities offered therein, and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">(h) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as
expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling
person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its
counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">5 </P>

</DIV></Center>


<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
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<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of
the requirements for filing on <FONT STYLE="white-space:nowrap">Form&nbsp;S-8</FONT> and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, State of
California, on March&nbsp;28, 2024. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="7%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" COLSPAN="3"><FONT STYLE="font-size:11pt"><B>BOUNDLESS BIO, INC. </B></FONT></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Zachary D. Hornby</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">Zachary D. Hornby</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">President and Chief Executive Officer</TD></TR>
</TABLE></DIV> <P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES AND POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We, the undersigned officers and directors of Boundless Bio, Inc., hereby severally constitute and appoint Zachary D. Hornby and Jami Rubin,
and each of them singly (with full power to each of them to act alone), our true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, with full power of substitution and
resubstitution in each of them for him or her and in his or her name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement (or any other registration
statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933), and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and
Exchange Commission, granting unto said <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents, and each of them, full power and authority to do and perform each and every act and thing requisite
or necessary to be done in and about the premises, as full to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorneys-in-fact</FONT></FONT> and agents or any of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the
capacities held on the dates indicated. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">6 </P>

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<p style="margin-top:1em; margin-bottom:0em; page-break-before:always"> </p>
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<Center><DIV STYLE="width:8.5in" align="left">

<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>

<TD WIDTH="38%"></TD>

<TD VALIGN="bottom"></TD>
<TD WIDTH="44%"></TD>

<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="16%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Signature</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Date</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Zachary D. Hornby</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">President, Chief Executive Officer, and Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(principal executive officer)</P></TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Zachary D. Hornby</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Jami Rubin</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Chief Financial Officer</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">(principal financial and accounting officer)</P></TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Jami Rubin</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Jonathan E. Lim, M.D.</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Chairman</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Jonathan E. Lim, M.D.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Christine Brennan, Ph.D.</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Director</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Christine Brennan, Ph.D.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Kristina Burow</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Director</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Kristina Burow</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ James Christensen, Ph.D.</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Director</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">James Christensen, Ph.D.</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Jennifer Lew</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Director</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Jennifer Lew</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Nancy Whiting, Pharm.D.</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" ALIGN="center">Director</TD>
<TD VALIGN="bottom" ROWSPAN="2">&nbsp;</TD>
<TD VALIGN="top" ROWSPAN="2" NOWRAP ALIGN="center">March&nbsp;28, 2024</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center">Nancy Whiting, Pharm.D.</TD></TR>
</TABLE> <P STYLE="font-size:18pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">7 </P>

</DIV></Center>

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{"company-data": {"conformed-name": "Boundless Bio, Inc.", "cik": "0001782303", "assigned-sic": "2834", "organization-name": "03 Life Sciences", "irs-number": "830751369", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-278354", "film-number": "24800586"}, "business-address": {"street1": "9880 CAMPUS POINT DRIVE", "street2": "SUITE 120", "city": "SAN DIEGO", "state": "CA", "zip": "92121", "phone": "(858) 766-9912"}, "mail-address": {"street1": "9880 CAMPUS POINT DRIVE", "street2": "SUITE 120", "city": "SAN DIEGO", "state": "CA", "zip": "92121"}}
S-8
As filed with the Securities and Exchange Commission on March 28, 2024
Registration
No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM
S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
BOUNDLESS BIO, INC.
(Exact name of registrant as specified in its charter)
Delaware
83-0751369
(State or Other Jurisdiction
of Incorporation or Organization)
(I.R.S. Employer
Identification No.)
9880 Campus Point Drive, Suite 120
San Diego, CA 92121
(858)
766-9912
(Address of Principal Executive Offices)
Boundless
Bio, Inc. 2018 Equity Incentive Plan
Boundless Bio, Inc. 2024 Incentive Award Plan
Boundless Bio, Inc. 2024 Employee Stock Purchase Plan
(Full Title of the Plans)
Zachary
Hornby
President and Chief Executive Officer
Boundless Bio, Inc.
9880
Campus Point Drive, Suite 120
San Diego, CA 92121
(858)
766-9912
(Name, Address and Telephone Number, Including Area Code, of Agent for Service)
Copies to:
Cheston J. Larson
Matthew T. Bush
Latham & Watkins LLP
12670 High Bluff Drive
San Diego, CA 92130
(858)
523-5400
Indicate by
check mark whether the registrant is a large accelerated filer, an accelerated filer, a
non-accelerated
filer, a smaller reporting company or an emerging growth company. See the definitions of "large
accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule
12b-2
of the Exchange Act.
Large accelerated filer
☐
Accelerated filer
☐
Non-accelerated filer
☒
Smaller reporting company
☒
Emerging growth company
☒
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended
transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐
Proposed sales to take place as soon after the effective date of the registration statement as awards granted under the above-named plans
are granted, exercised and/or distributed.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
The documents containing the information specified in Part I of Form
S-8
will be sent or given to
participants as specified by Rule 428(b)(1) of the Securities Act. These documents and the documents incorporated by reference into this registration statement pursuant to Item 3 of Part II of this registration statement, taken
together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
In this registration statement, Boundless Bio, Inc. is sometimes referred to as "Registrant," "we," "us" or
"our."
Item 3. Incorporation of Documents by Reference.
The Securities and Exchange Commission ("SEC") allows us to "incorporate by reference" the information we file with them,
which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this registration statement, and later information filed with the SEC will
update and supersede this information. We hereby incorporate by reference into this registration statement the following documents previously filed with the SEC:
(a)
The prospectus filed by the Registrant with the SEC pursuant to
Rule
 424(b)
under the Securities Act, on March 28, 2024 relating to the registration statement on Form
S-1,
as amended (Registration
No. 333-277696),
which
contains the Registrant's audited financial statements for the latest fiscal year for which such statements have been filed; and
(b)
The description of the Registrant's common stock set forth in the Registrant's registration statement
on
Form 8-A12B
(Registration No. 001-41989), filed by the Registrant with the SEC under
Section 12(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), on March 22, 2024, including any amendments or reports filed for the purpose of updating such description.
In addition, all documents filed by the Registrant pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the
filing of this registration statement and prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which
de-registers
all securities then remaining
unsold shall be deemed to be incorporated by reference into this registration statement and to be a part hereof from the date of filing such documents, except as to specific sections of such statements as set forth therein. Any statement contained
in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement contained herein or in any other subsequently filed
document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any statement contained herein shall be deemed to be modified or superseded for purposes of this registration statement to
the extent that a statement contained in any subsequently filed document which also is incorporated or deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be
deemed, except as so modified or superseded, to constitute a part of this registration statement.
Under no circumstances shall any
information furnished under Item 2.02 or 7.01 of Form
8-K
be deemed incorporated herein by reference unless such Form
8-K
expressly provides to the contrary.
2
Item 4. Description of Securities.
Not applicable.
Item 5. Interests of
Named Experts and Counsel.
Not applicable.
Item 6. Indemnification of Directors and Officers.
Section 102 of the General Corporation Law of the State of Delaware permits a corporation to eliminate the personal liability of directors of a
corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly
violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Our certificate of incorporation provides that no director of the Registrant shall
be personally liable to it or its stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability, except to the extent that the General Corporation Law of the State of
Delaware prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty.
Section 145 of the
General Corporation Law of the State of Delaware provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation, or a person serving at the request of the corporation for another corporation,
partnership, joint venture, trust or other enterprise in related capacities against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with an
action, suit or proceeding to which he was or is a party or is threatened to be made a party to any threatened, ending or completed action, suit or proceeding by reason of such position, if such person acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful, except that, in the case of actions brought by or in the
right of the corporation, no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or other
adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other
court shall deem proper.
Our amended and restated certificate of incorporation and our amended and restated bylaws provide that we will
indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or proceeding (other than an action by or in the right of us) by reason of the fact that he or she is or was, or has
agreed to become, a director or officer, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or
other enterprise (all such persons being referred to as an "Indemnitee"), or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys' fees), judgments, fines and
amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding and any appeal therefrom, if such Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed
to, our best interests, and, with respect to any criminal action or proceeding, he or she had no reasonable cause to believe his or her conduct was unlawful. Our amended and restated certificate of incorporation and our amended and restated bylaws,
each as currently in effect, provide that we will indemnify any Indemnitee who was or is a party to an action or suit by or in the right of us to procure a judgment in our favor by reason of the fact that the Indemnitee is or was, or has agreed to
become, a director or officer, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other
enterprise, or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys' fees) and, to the extent permitted by law, amounts paid in settlement actually and reasonably incurred in
connection with such action, suit or
3
proceeding, and any appeal therefrom, if the Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, our best interests, except that no
indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to us, unless a court determines that, despite such adjudication but in view of all of the circumstances, he or
she is entitled to indemnification of such expenses. Notwithstanding the foregoing, to the extent that any Indemnitee has been successful, on the merits or otherwise, he or she will be indemnified by us against all expenses (including
attorneys' fees) actually and reasonably incurred in connection therewith. Expenses must be advanced to an Indemnitee under certain circumstances.
We have entered into indemnification agreements with each of our directors and officers. These indemnification agreements may require us,
among other things, to indemnify our directors and officers for some expenses, including attorneys' fees, judgments, fines and settlement amounts incurred by a director or officer in any action or proceeding arising out of his or her service as
one of our directors or officers, or any of our subsidiaries or any other company or enterprise to which the person provides services at our request.
We maintain a general liability insurance policy that covers certain liabilities of directors and officers of our corporation arising out of
claims based on acts or omissions in their capacities as directors or officers.
Item 7. Exemption from Registration Claimed.
Not applicable.
Item 8. Exhibits.
Exhibit
Number
Exhibit Description
Incorporated by Reference
Filed
Herewith
Form
File No.
Exhibit
Filing Date
3.1
Form of Amended and Restated Certificate of Incorporation
S-1/A
333— 277696
3.3
March 21, 2024
3.2
Form of Amended and Restated Bylaws
S-1/A
333— 277696
3.4
March 21, 2024
4.1
Specimen stock certificate evidencing the shares of common stock
S-1/A
333— 277696
4.1
March 21, 2024
5.1
Opinion of Latham & Watkins LLP
X
10.1
Boundless Bio, Inc. 2018 Equity Incentive Plan, as amended, and form of stock option agreement and form of restricted stock agreement thereunder
S-1
333— 277696
10.1
March 6, 2024
10.2
Boundless Bio, Inc. 2024 Incentive Award Plan and form of stock option agreement and form of restricted stock unit agreement thereunder
X
10.3
Boundless Bio, Inc. 2024 Employee Stock Purchase Plan
X
23.1
Consent of Independent Registered Public Accounting Firm
X
23.2
Consent of Latham & Watkins LLP (included in Exhibit 5.1)
X
24.1
Power of Attorney (see signature page)
X
107
Calculation of Filing Fee Table
X
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Item 9. Undertakings.
(a) The undersigned Registrant hereby undertakes:
(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement,
(i) to include any prospectus required by Section 10(a)(3) of the Securities Act;
(ii) to reflect in the prospectus any facts or events arising after the effective date of this registration statement (or the
most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with
the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the "Calculation of Filing Fee Tables" table in the effective
registration statement; and
(iii) to include any material information with respect to the plan of distribution not
previously disclosed in this registration statement or any material change to such information in this registration statement;
provided, however
,
that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if this registration statement is on Form
S-8
and the information required to be included in a post-effective amendment by those paragraphs is contained in
reports filed with or furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this registration statement.
(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a
new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the
termination of the offering.
(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the
Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to
Section 15(d) of the Exchange Act) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement, relating to the securities offered therein, and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof.
(h) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as
expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling
person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its
counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.
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SIGNATURES
Pursuant to the requirements of the Securities Act, the Registrant certifies that it has reasonable grounds to believe that it meets all of
the requirements for filing on
Form S-8
and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, State of
California, on March 28, 2024.
BOUNDLESS BIO, INC.
By:
/s/ Zachary D. Hornby
Zachary D. Hornby
President and Chief Executive Officer
SIGNATURES AND POWER OF ATTORNEY
We, the undersigned officers and directors of Boundless Bio, Inc., hereby severally constitute and appoint Zachary D. Hornby and Jami Rubin,
and each of them singly (with full power to each of them to act alone), our true and lawful
attorneys-in-fact
and agents, with full power of substitution and
resubstitution in each of them for him or her and in his or her name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement (or any other registration
statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933), and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and
Exchange Commission, granting unto said
attorneys-in-fact
and agents, and each of them, full power and authority to do and perform each and every act and thing requisite
or necessary to be done in and about the premises, as full to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said
attorneys-in-fact
and agents or any of them, or their or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the
capacities held on the dates indicated.
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Signature
Title
Date
/s/ Zachary D. Hornby
President, Chief Executive Officer, and Director
(principal executive officer)
March 28, 2024
Zachary D. Hornby
/s/ Jami Rubin
Chief Financial Officer
(principal financial and accounting officer)
March 28, 2024
Jami Rubin
/s/ Jonathan E. Lim, M.D.
Chairman
March 28, 2024
Jonathan E. Lim, M.D.
/s/ Christine Brennan, Ph.D.
Director
March 28, 2024
Christine Brennan, Ph.D.
/s/ Kristina Burow
Director
March 28, 2024
Kristina Burow
/s/ James Christensen, Ph.D.
Director
March 28, 2024
James Christensen, Ph.D.
/s/ Jennifer Lew
Director
March 28, 2024
Jennifer Lew
/s/ Nancy Whiting, Pharm.D.
Director
March 28, 2024
Nancy Whiting, Pharm.D.
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