Exhibit 10.4

FORM OF REGISTRATION RIGHTS AGREEMENT

THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”), dated as of October 7, 2025, is entered into by and among Zenas BioPharma, Inc., a Delaware corporation (the “Company”), and the several investors signatory hereto (individually as an “Investor” and collectively together with their respective permitted assigns, the “Investors”). Capitalized terms used herein and not otherwise defined herein shall have the respective meanings set forth in the Securities Purchase Agreement by and among the parties hereto, dated as of the date hereof (as amended, restated, supplemented or otherwise modified from time to time, the “Purchase Agreement”).

WHEREAS:

A.            Upon the terms and subject to the conditions of the Purchase Agreement, the Company has agreed to issue to the Investors, and the Investors have agreed to purchase, severally and not jointly, an aggregate of up to $119,995,907.30 of shares (the “Shares”) of the Company's common stock, par value $0.0001 per share (the “Common Stock”) pursuant to the Purchase Agreement.

B.            To induce the Investors to enter into the Purchase Agreement, the Company has agreed to provide certain registration rights under the U.S. Securities Act of 1933, as amended, and the rules and regulations thereunder, or any similar successor statute (collectively, the “Securities Act”), and applicable state securities laws.

NOW, THEREFORE, in consideration of the promises and the mutual covenants contained herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company and the Investors hereby agree as follows:

DEFINITIONS.

For purposes of this Agreement, the following terms shall have the following meanings:

(a)            “Person” means an individual, partnership, corporation, limited liability company, business trust, joint stock company, trust, unincorporated association, joint venture or any other entity or organization.

(b)            “Prospectus” means (i) the prospectus included in any Registration Statement, as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by such Registration Statement and by all other amendments and supplements to the prospectus, including post-effective amendments and all material incorporated by reference in such prospectus, and (ii) any “free writing prospectus” as defined in Rule 405 under the Securities Act, relating to the terms of the offering of any portion of the Registrable Securities.

(c)            “Register,” “Registered,” and “Registration” refer to a registration effected by preparing and filing one or more registration statements of the Company in compliance with the Securities Act and providing for offering securities on a continuous basis, and the declaration or ordering of effectiveness of such registration statement(s) by the U.S. Securities and Exchange Commission (the “SEC”).

(d)            “Registrable Securities” means the Shares and any Common Stock issued or issuable with respect to the Shares as a result of any stock split or subdivision, stock dividend, recapitalization, exchange or similar event. Registrable Securities shall cease to be Registrable Securities with respect to each Investor upon the earlier of (i) the date on which such Investor shall have resold all the Registrable Securities held by such Investor covered by the Registration Statement and (ii) the date on which the Registrable Securities may be sold by such Investor under Rule 144(b)(1)(i) of the Securities Act in any ninety (90) day period without volume or manner of sale limitations.

(e)            “Registration Expenses” means all registration and filing fee expenses incurred by the Company in effecting any registration pursuant to this Agreement, including (i) all registration, qualification, and filing fees, printing expenses, and any other fees and expenses associated with filings required to be made with the SEC, FINRA or any other regulatory authority, (ii) all fees and expenses in connection with compliance with or clearing the Registrable Securities for sale under any securities or “Blue Sky” laws, (iii) all printing, duplicating, word processing, messenger, telephone, facsimile and delivery expenses, and (iv) all fees and disbursements of counsel for the Company and of all independent certified public accountants of the Company (including the expenses of any special audit and cold comfort letters required by or incident to such performance).

(f)            “Registration Statement” means any registration statement of the Company filed with, or to be filed with, the SEC under the Securities Act, that Registers Registrable Securities, including the related Prospectus, amendments and supplements to such registration statement, including pre- and post-effective amendments, and all exhibits and all material incorporated by reference in such registration statement as may be necessary to comply with applicable securities laws. “Registration Statement” shall also include a New Registration Statement, as amended when each became effective, including all documents filed as part thereof or incorporated by reference therein, and including any information contained in a Prospectus subsequently filed with the SEC.

(g)            “Required Investors” means the Investors holding a majority of the Registrable Securities outstanding from time to time.

(h)            “Selling Expenses” means all underwriting discounts and selling commissions applicable to the sale of Registrable Securities and all similar fees and commissions relating to the Investors’ disposition of the Registrable Securities.

REGISTRATION.

(a)            Mandatory Registration. The Company shall, as promptly as reasonably practicable and in any event no later than 15 days after the Closing Date (the “Filing Deadline”), prepare and file with the SEC an initial Registration Statement (the “Initial Registration Statement”) covering the resale of all Registrable Securities. The Initial Registration Statement shall be designated by the Company as an “automatic shelf registration statement” (as defined in Rule 405 of the Securities Act) if the Company is a “well-known seasoned issuer” (as defined in Rule 405 of the Securities Act) at the time of filing of the Initial Registration Statement with the SEC. Before filing the Registration Statement, the Company shall furnish to the Investors a copy of the Registration Statement. The Investors and their counsel shall have at least three Business Days prior to the anticipated filing date of a Registration Statement to review and comment upon such Registration Statement and any amendment or supplement to such Registration Statement and any related Prospectus, prior to its filing with the SEC. Subject to any SEC comments, such Registration Statement shall include the plan of distribution substantially in the form attached hereto as Exhibit A. Such Registration Statement also shall cover, to the extent allowable under the Securities Act and the rules promulgated thereunder (including Rule 416), such indeterminate number of additional shares of Common Stock resulting from stock splits, stock dividends or similar transactions with respect to the Registrable Securities. Such Registration Statement shall not include any shares of Common Stock or other securities for the account of any other holder of securities of the Company without the prior written consent of the Required Investors. The Company shall (a) use commercially reasonable efforts to address in each such document prior to being so filed with the SEC such comments as the Investor or its counsel reasonably proposed by the Investor, and (b) not file any Registration Statement or Prospectus or any amendment or supplement thereto containing information regarding the Investor to which Investor reasonably objects, unless such information is required to comply with any applicable law or regulation. The Investors shall furnish all information reasonably requested by the Company and as shall be reasonably required in connection with any registration referred to in this Agreement.

(b)            Effectiveness. The Company shall use its reasonable best efforts to have the Initial Registration Statement and any amendment declared effective by the SEC at the earliest possible date but no later than the earlier of the 75th calendar day following the initial filing date of the Initial Registration Statement if the SEC notifies the Company that it will “review” the Initial Registration Statement and (b) the fifth Business Day after the date the Company is notified (orally or in writing, whichever is earlier) by the SEC that the Initial Registration Statement will not be “reviewed” or will not be subject to further review (the “Effectiveness Deadline”). The Company shall notify the Investor by e-mail as promptly as practicable, and in any event, within 24 hours, after the Initial Registration Statement is declared effective or is supplemented and shall provide the Investor with copies of any Prospectus to be used in connection with the sale or other disposition of the securities covered thereby. The Company shall use reasonable best efforts to keep the Initial Registration Statement continuously effective pursuant to Rule 415 promulgated under the Securities Act and available for the resale by the Investors of all of the Registrable Securities covered thereby at all times until the earlier to occur of the following events: (i) the date on which the Investors shall have resold all the Registrable Securities covered thereby; and (ii) the date on which the Registrable Securities may be resold by the Investors without registration and without regard to any volume or manner-of-sale limitations by reason of Rule 144, without the requirement for the Company to be in compliance with the current public information requirement under Rule 144 under the Securities Act or any other rule of similar effect (the “Registration Period”). The Initial Registration Statement (including any amendments or supplements thereto and prospectuses contained therein) shall not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein, or necessary to make the statements therein, in light of the circumstances in which they were made, not misleading.

(c)            Sufficient Number of Shares Registered. In the event the number of shares available under the Initial Registration Statement at any time is insufficient to cover the Registrable Securities, the Company shall, to the extent necessary and permissible, amend the Initial Registration Statement or file a new registration statement (together with any prospectuses or prospectus supplements thereunder, a “New Registration Statement”), so as to cover all of such Registrable Securities as soon as reasonably practicable, but in any event not later than ten Business Days after the necessity therefor arises (the “New Registration Filing Deadline”). The Company shall use its reasonable best efforts to have such amendment and/or New Registration Statement become effective as soon as reasonably practicable following the filing thereof but no later than the earlier of the 75th calendar day following the initial filing date of the New Registration Statement if the SEC notifies the Company that it will “review” the New Registration Statement and (b) the fifth Business Day after the date the Company is notified (orally or in writing, whichever is earlier) by the SEC that the New Registration Statement will not be “reviewed” or will not be subject to further review (the earlier of such dates, the “New Registration Effectiveness Deadline”). The provisions of Section 2(a) and (b) shall apply to the New Registration Statement, except as modified hereby.

(d)            Allowable Delays. On no more than two occasions and for not more than 30 consecutive days or for a total of not more than 60 days in any 12 month period, the Company may delay the effectiveness of the Initial Registration Statement or any other Registration Statement, or suspend the use of any Prospectus, in the event that the Company or Board of Directors determines, in good faith and upon advice of legal counsel, that such delay or suspension is necessary to (A) delay the disclosure of material non-public information concerning the Company, the disclosure of which at the time is not, in the good faith opinion of the Company, in the best interests of the Company or (B) amend or supplement the affected Registration Statement or the related Prospectus so that such Registration Statement or Prospectus shall not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the case of the Prospectus in light of the circumstances under which they were made, not misleading (an “Allowed Delay”); provided, that the Company shall promptly (a) notify each Investor in writing of the commencement of an Allowed Delay, but shall not (without the prior written consent of an Investor) disclose to such Investor any material non-public information giving rise to an Allowed Delay, (b) advise the Investors in writing to cease all sales under the applicable Registration Statement until the end of the Allowed Delay and (c) use commercially reasonable efforts to terminate an Allowed Delay as promptly as practicable.

(e)            Rule 415; Cutback. If at any time the SEC takes the position that the offering of some or all of the Registrable Securities in any Registration Statement is not eligible to be made on a delayed or continuous basis under the provisions of Rule 415 under the Securities Act (provided, however, the Company shall be obligated to use reasonable best efforts to advocate with the SEC for the registration of all of the Registrable Securities) or requires any Investor to be named as an “underwriter,” the Company shall (i) promptly notify each holder of Registrable Securities thereof and (ii) make commercially reasonable efforts to persuade the SEC that the offering contemplated by such Registration Statement is a valid secondary offering and not an offering “by or on behalf of the issuer” as defined in Rule 415 and that none of the Investors is an “underwriter.” The Investors shall have the right to select one legal counsel, which counsel shall be selected by the Required Investors (provided that an Investor may elect to be represented by its own legal counsel at such Investor’s own expense), to review and oversee any registration or matters pursuant to this Section 2(f), including participation in any meetings or discussions with the SEC regarding the SEC’s position and to comment on any written submission made to the SEC with respect thereto. No such written submission with respect to this matter shall be made to the SEC to which any Investor’s counsel reasonably objects. In the event that, despite the Company’s reasonable best efforts and compliance with the terms of this Section 2(f), the SEC refuses to alter its position, the Company shall (i) remove from such Registration Statement such portion of the Registrable Securities (the “Cut Back Shares”) and/or (ii) agree to such restrictions and limitations on the registration and resale of the Registrable Securities as the SEC may require to assure the Company’s compliance with the requirements of Rule 415 (collectively, the “SEC Restrictions”); provided, however, that the Company shall not name any Investor as an “underwriter” in such Registration Statement without the prior written consent of such Investor (provided that, in the event an Investor withholds such consent, the Company shall have no obligation hereunder to include any Registrable Securities of such Investor in any Registration Statement covering the resale thereof until such time as the SEC no longer requires such Investor to be named as an “underwriter” in such Registration Statement or such Investor otherwise consents in writing to being so named). Any cut-back imposed on the Investors pursuant to this Section 2(f) shall be allocated among the Investors on a pro rata basis and shall be applied first to any of the Registrable Securities of such Investor as such Investor shall designate, unless the SEC Restrictions otherwise require or provide or the Investors otherwise agree.

RELATED COMPANY OBLIGATIONS.

With respect to the Registration Statement and whenever any Registrable Securities are to be Registered pursuant to Section 2, including on the Initial Registration Statement or on any New Registration Statement, the Company shall use its reasonable best efforts to effect the registration of the Registrable Securities in accordance with the intended method of disposition thereof and, pursuant thereto, the Company shall have the following obligations:

(a)            Notifications. The Company will promptly notify the Investors of the time when any subsequent amendment to the Initial Registration Statement or any New Registration Statement, other than documents incorporated by reference, has been filed with the SEC and/or has become effective or where a receipt has been issued therefor or any subsequent supplement to a Prospectus has been filed and of any request by the SEC for any amendment or supplement to the Registration Statement, any New Registration Statement or any Prospectus or for additional information.

(b)            Amendments. The Company will prepare and file with the SEC any amendments, post-effective amendments or supplements to the Initial Registration Statement, any New Registration Statement or any Prospectus, as applicable, that, (a) as may be necessary to keep such Registration Statement effective for the Registration Period and to comply with the provisions of the Securities Act and the Securities Exchange Act of 1934, as amended (the “Exchange Act”) with respect to the distribution of all of the Registrable Securities covered thereby, or (b) in the reasonable opinion of the Investors and the Company, as may be necessary or advisable in connection with any acquisition or sale of Registrable Securities by the Investors.

(c)            Investor Review. The Company will not file any amendment or supplement to the Registration Statement, any New Registration Statement or any Prospectus, other than documents incorporated by reference, relating to the Investors, the Registrable Securities or the transactions contemplated hereby unless (A) the Investors and their counsel shall have been advised and afforded the opportunity to review and comment thereon at least three (3) Business Days prior to filing with the SEC and (B) the Company shall have given reasonable due consideration to any comments thereon received from the Investors or their counsel.

(d)            Copies Available. The Company will furnish to any Investor whose Registrable Securities are included in any Registration Statement and its counsel copies of the Initial Registration Statement, any Prospectus thereunder (including all documents incorporated by reference therein), any Prospectus supplement thereunder, any New Registration Statement and all amendments to the Initial Registration Statement or any New Registration Statement that are filed with the SEC during the Registration Period (including all documents filed with or furnished to the SEC during such period that are deemed to be incorporated by reference therein), each letter written by or on behalf of the Company to the SEC or the staff of the SEC, and each item of correspondence from the SEC or the staff of the SEC, in each case relating to such Registration Statement (other than any portion thereof which contains information for which the Company has sought confidential treatment) and such other documents as Investor may reasonably request in order to facilitate the disposition of the Registrable Securities owned by Investor that are covered by such Registration Statement, in each case as soon as reasonably practicable upon such Investor’s request and in such quantities as such Investor may from time to time reasonably request; provided, however, that the Company shall not be required to furnish any document to the Investor to the extent such document is available on EDGAR.

(e)            Notification of Stop Orders; Material Changes. The Company shall use commercially reasonable efforts to (i) prevent the issuance of any stop order or other suspension of effectiveness and, (ii) if such order is issued, obtain the withdrawal of any such order as soon as practicable. The Company shall advise the Investors promptly (but in no event later than 24 hours) and shall confirm such advice in writing, in each case: (i) of the Company’s receipt of notice of any request by the SEC or any other federal or state governmental authority for amendment of or a supplement to the Registration Statement or any Prospectus or for any additional information; (ii) of the Company’s receipt of notice of the issuance by the SEC or any other federal or state governmental authority of any stop order suspending the effectiveness of the Initial Registration Statement or prohibiting or suspending the use of any Prospectus or Prospectus supplement, or any New Registration Statement, or of the Company’s receipt of any notification of the suspension of qualification of the Registrable Securities for offering or sale in any jurisdiction or the initiation or contemplated initiation of any proceeding for such purpose; and (iii) of the Company becoming aware of the happening of any event, which makes any statement of a material fact made in any Registration Statement or any Prospectus untrue or which requires the making of any additions to or changes to the statements then made in any Registration Statement or any Prospectus in order to state a material fact required by the Securities Act to be stated therein or necessary in order to make the statements then made therein (in the case of any Prospectus, in light of the circumstances under which they were made) not misleading, or of the necessity to amend any Registration Statement or any Prospectus to comply with the Securities Act or any other law. The Company shall not be required to disclose to the Investors the substance of specific reasons of any of the events set forth in clause (i) to (iii) of the immediately preceding sentence (each, a “Suspension Event”), but rather, shall only be required to disclose that the event has occurred. If at any time the SEC, or any other federal or state governmental authority shall issue any stop order suspending the effectiveness of any Registration Statement or prohibiting or suspending the use of any Prospectus or Prospectus supplement, the Company shall use its reasonable best efforts to obtain the withdrawal of such order at the earliest practicable time. The Company shall furnish to the Investors, without charge, a copy of any correspondence from the SEC or the staff of the SEC, or any other federal or state governmental authority to the Company or its representatives relating to the Initial Registration Statement, any New Registration Statement or any Prospectus, or Prospectus supplement as the case may be. In the event of a Suspension Event set forth in clause (iii) of the first sentence of this Section 3(e), the Company will use its commercially reasonable efforts to publicly disclose such event as soon as reasonably practicable, or otherwise resolve the matter such that sales under Registration Statements may resume; provided, however, that if the Company has a bona fide business purpose for not making such information public, the Company may suspend the use of all Registration Statements for up to 60 consecutive calendar days; provided, further, that the Company may not suspend the use of all Registration Statements more than twice, or for more than 90 total calendar days, in each case during any twelve-month period.

(f)            Confirmation of Effectiveness. If reasonably requested by an Investor at any time in respect of any Registration Statement, the Company shall deliver to such Investor a written confirmation (email being sufficient) from Company’s counsel of whether or not the effectiveness of such Registration Statement has lapsed at any time for any reason (including, without limitation, the issuance of a stop order) and whether or not such Registration Statement is currently effective and available to the Company for sale of Registrable Securities.

(g)            Listing. The Company shall use best efforts to cause all Registrable Securities covered by a Registration Statement to be listed on the Nasdaq Global Select Market.

(h)            Compliance. The Company shall otherwise use best efforts to comply with all applicable rules and regulations of the SEC under the Securities Act and the Exchange Act, including, without limitation, Rule 172 under the Securities Act, file any final prospectus, including any supplement or amendment thereof, with the SEC pursuant to Rule 424 under the Securities Act, promptly inform the Investor in writing if, at any time during the Registration Period, the Company does not satisfy the conditions specified in Rule 172 and, as a result thereof, the Investor is required to deliver a prospectus in connection with any disposition of Registrable Securities and take such other actions as may be reasonably necessary to facilitate the registration of the Registrable Securities hereunder, and make available to its security holders, as soon as reasonably practicable, but not later than the Availability Date (as defined below), an earnings statement covering a period of at least 12 months, beginning after the effective date of each Registration Statement, which earnings statement shall satisfy the provisions of Section 11(a) of the Securities Act, including Rule 158 promulgated thereunder (for the purpose of this subsection 3(h), “Availability Date” means the 45^th day following the end of the fourth fiscal quarter that includes the effective date of such Registration Statement, except that, if such fourth fiscal quarter is the last quarter of the Company’s fiscal year, “Availability Date” means the 90^th day after the end of such fourth fiscal quarter).

(i)            Blue-Sky. The Company shall register or qualify or cooperate with the Investor and their counsel in connection with the registration or qualification of such Registrable Securities for the offer and sale under the securities or blue sky laws of such jurisdictions reasonably requested by the Investor; provided, however, that the Company shall not be required in connection therewith or as a condition thereto to (i) qualify to do business in any jurisdiction where it would not otherwise be required to qualify but for this Section 3(i), (ii) subject itself to general taxation in any jurisdiction where it would not otherwise be so subject but for this Section 3(i), or (iii) file a general consent to service of process in any such jurisdiction.

(j)            Rule 144. With a view to making available to the Investors the benefits of Rule 144 (or its successor rule) and any other rule or regulation of the SEC that may at any time permit the Investors to sell shares of Common Stock to the public without registration, the Company covenants and agrees to: (i) make and keep adequate current public information available, as those terms are understood and defined in Rule 144, until the earlier of (A) six months after such date as all of the Registrable Securities may be sold without restriction by the holders thereof pursuant to Rule 144 or any other rule of similar effect or (B) such date as there are no longer Registrable Securities; and (ii) file with the SEC in a timely manner all reports and other documents required of the Company under the Exchange Act; (iii) furnish electronically to each Investor upon request, as long as such Investor owns any Registrable Securities, (A) a written statement by the Company that it has complied with the reporting requirements of the Exchange Act, (B) a copy of or electronic access to the Company’s most recent Annual Report on Form 10-K or Quarterly Report on Form 10-Q, and (C) such other information as may be reasonably requested in order to avail such Investor of any rule or regulation of the SEC that permits the selling of any such Registrable Securities without registration.

(k)            Cooperation. The Company shall cooperate with the holders of the Registrable Securities to facilitate the timely preparation and delivery of certificates or uncertificated shares representing the Registrable Securities to be sold pursuant to such Registration Statement or Rule 144 free of any restrictive legends and representing such number of shares of Common Stock and registered in such names as the holders of the Registrable Securities may reasonably request to the extent permitted by such Registration Statement or Rule 144 to effect sales of Registrable Securities; for the avoidance of doubt, the Company may satisfy its obligations hereunder without issuing physical stock certificates through the use of The Depository Trust Company’s Direct Registration System.

OBLIGATIONS OF THE INVESTORS.

(a)            Investor Information. Each Investor shall provide a completed Investor Questionnaire in the form attached hereto as Exhibit B or such other form or information required by the Company in connection with the registration of the Registrable Securities. If the Company has not received such completed Questionnaire from an Investor within three Business Days of the Company’s request, the Company may file the Registration Statement without including such Investor’s Registrable Securities.

(b)            Suspension of Sales. Each Investor, severally and not jointly with any other Investor, agrees that, upon receipt of any notice from the Company of the existence of an Allowed Delay or a Suspension Event as set forth in Section 3(e), the Investor will promptly discontinue disposition of Registrable Securities pursuant to any Registration Statement covering such Registrable Securities until the Investor's receipt of a notice from the Company confirming the resolution of such Allowed Delay or Suspension Event and that such dispositions may again be made; provided, for the avoidance of doubt, that the foregoing shall not limit the right of the Investor to sell or otherwise dispose of the Registrable Securities pursuant to Rule 144 or any other exemption from the registration requirements of the Securities Act or to settle a transaction pursuant to a Registration Statement as to which a contract for such sale was entered into prior to such Investor’s receipt of the notice from the Company of the existence of the Allowed Delay or Suspension Event. The Company shall cause its transfer agent to deliver unlegended shares of Common Stock to a transferee of an Investor in accordance with any sale of Registrable Securities pursuant to a Registration Statement with respect to which such Investor has entered into a contract for sale prior to such Investor’s receipt of the notice from the Company of the existence of the Allowed Delay or Suspension Event.

(c)            Investor Cooperation. Each Investor, severally and not jointly with any other Investor, agrees to cooperate with the Company as reasonably requested by the Company in connection with the preparation and filing of any amendments and supplements to any Registration Statement or New Registration Statement hereunder, unless such Investor has notified the Company in writing of its election to exclude all of its Registrable Securities from such Registration Statement.

EXPENSES OF REGISTRATION.

All Registration Expenses incurred in connection with registrations pursuant to this Agreement shall be borne by the Company. All Selling Expenses relating to securities registered on behalf of an Investor shall be borne by such Investor.

INDEMNIFICATION.

(a)            To the fullest extent permitted by law, the Company will, and hereby does, indemnify, hold harmless and defend the Investors, each Person, if any, who controls the Investors, the members, the directors, officers, partners, employees, members, managers, agents, representatives and advisors of the Investors and each Person, if any, who controls the Investors within the meaning of the Securities Act or the Exchange Act (each, an “Indemnified Person”), against any losses, obligation, claims, damages, liabilities, contingencies, judgments, fines, penalties, charges, costs (including, without limitation, court costs and costs of preparation), reasonable and documented attorneys’ fees, amounts paid in settlement or reasonable and documented expenses, (collectively, “Claims”) reasonably incurred in investigating, preparing or defending any action, claim, suit, inquiry, proceeding, investigation or appeal taken from the foregoing by or before any court or governmental, administrative or other regulatory agency or body or the SEC, whether pending or threatened, whether or not an indemnified party is or may be a party thereto (“Indemnified Damages”), to which any of them may become subject insofar as such Claims (or actions or proceedings, whether commenced or threatened, in respect thereof) arise out of or are based upon: (i) any untrue statement or alleged untrue statement or omission or alleged omission of any material fact contained in any Registration Statement, any preliminary prospectus or final prospectus, or any amendment or supplement thereof, or (ii) any violation or alleged violation by the Company or any of its Subsidiaries of the Securities Act, Exchange Act or any other state securities or other “blue sky” laws of any jurisdiction in which Registrable Securities are offered or any rule or regulation promulgated thereunder applicable to the Company or its agents and relating to action or inaction required of the Company in connection with such registration of the Registrable Securities (the matters in the foregoing clauses (i) and (ii) being, collectively, “Violations”). The Company shall reimburse each Indemnified Person promptly as such expenses are incurred and are due and payable, for any reasonable out-of-pocket legal fees or other reasonable and documented expenses incurred by them in connection with investigating or defending any such Claim. Notwithstanding anything to the contrary contained herein, the indemnification agreement contained in this Section 6(a): (A) shall not apply to a Claim by an Indemnified Person arising out of or based upon a Violation which occurs in reliance upon and in conformity with information furnished in writing to the Company by the Investors or such Indemnified Person specifically for use in such Registration Statement or prospectus and was reviewed and approved in writing by such Investor or such Indemnified Person expressly for use in connection with the preparation of any Registration Statement, any prospectus or any such amendment thereof or supplement thereto, if such in each case if the foregoing was timely made available by the Company; (B) with respect to any superseded prospectus, shall not inure to the benefit of any such Person from whom the Person asserting any such Claim purchased the Registrable Securities that are the subject thereof (or to the benefit of any other Indemnified Person) if the untrue statement or omission of material fact contained in the superseded prospectus was corrected in the revised prospectus, as then amended or supplemented, and the Indemnified Person was promptly advised in writing not to use the outdated, defective or incorrect prospectus prior to the use giving rise to a Violation; (C) shall not apply to amounts paid in settlement of any Claim if such settlement is effected without the prior written consent of the Company, which consent shall not be unreasonably withheld, conditioned or delayed. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of the Indemnified Person and shall survive the transfer of the Registrable Securities by the Investor pursuant to Section 8.

(b)            In connection with the Initial Registration Statement, any New Registration Statement or any Prospectus, the Investors, severally and not jointly, agree to indemnify, hold harmless and defend, the Company, each of its directors, each of its officers who signed the Initial Registration Statement or signs any New Registration Statement, each Person, if any, who controls the Company within the meaning of the Securities Act or the Exchange Act (each, an “Indemnified Party”), against any losses, claims, damages, liabilities and expense (including reasonable attorney fees) resulting from any Violation, in each case to the extent, and only to the extent, that such Violation occurs in reliance upon and in conformity with information about an Investor furnished in writing by such Investor to the Company and reviewed and approved in writing by such Investor or such Indemnified Person expressly for use in connection with the preparation of the Registration Statement, any New Registration Statement, any prospectus or any such amendment thereof or supplement thereto. In no event shall the liability of an Investor be greater in amount than the dollar amount of the proceeds (net of all expense paid by such Investor in connection with any claim relating to this Section 6 and the amount of any damages such Investor has otherwise been required to pay by reason of such untrue statement or omission) received by such Investor upon the sale of the Registrable Securities included in such Registration Statement giving rise to such indemnification obligation. Such indemnity shall remain in full force and effect regardless of any investigation made by or on behalf of such Indemnified Party and shall survive the transfer of the Registrable Securities by any Investor pursuant to Section 8.

(c)            Promptly after receipt by an Indemnified Person or Indemnified Party under this Section 6 of notice of the commencement of any action or proceeding (including any governmental action or proceeding) involving a Claim, such Indemnified Person or Indemnified Party shall, if a Claim in respect thereof is to be made against any indemnifying party under this Section 6, deliver to the indemnifying party a written notice of the commencement thereof, and the indemnifying party shall have the right to participate in, and, to the extent the indemnifying party so desires, jointly with any other indemnifying party similarly noticed, to assume control of the defense thereof with counsel mutually satisfactory to the indemnifying party and the Indemnified Person or the Indemnified Party, as the case may be, and upon such notice, the indemnifying party shall not be liable to the Indemnified Person or the Indemnified Party for any legal or other expenses subsequently incurred by the Indemnified Person or the Indemnified Party in connection with the defense thereof; provided, however, that an Indemnified Person or Indemnified Party (together with all other Indemnified Persons and Indemnified Parties that may be represented without conflict by one counsel) shall have the right to retain its own counsel with the reasonable fees and expenses to be paid by the indemnifying party, if, in the reasonable opinion of counsel retained by the indemnifying party, the representation by such counsel of the Indemnified Person or Indemnified Party and the indemnifying party would be inappropriate due to actual or potential differing interests between such Indemnified Person or Indemnified Party and any other party represented by such counsel in such proceeding. The Indemnified Party or Indemnified Person shall cooperate with the indemnifying party in connection with any negotiation or defense of any such action or claim by the indemnifying party and shall furnish to the indemnifying party all information reasonably available to the Indemnified Party or Indemnified Person which relates to such action or claim. The indemnifying party shall keep the Indemnified Party or Indemnified Person fully apprised as to the status of the defense or any settlement negotiations with respect thereto. No indemnifying party shall be liable for any settlement of any action, claim or proceeding effected without its written consent, provided, however, that the indemnifying party shall not unreasonably withhold, delay or condition its consent. No indemnifying party shall, without the consent of the Indemnified Party or Indemnified Person, consent to entry of any judgment or enter into any settlement or other compromise unless such judgment or settlement (i) imposes no liability or obligation on, (ii) includes as an unconditional term thereof the giving of a complete, explicit and unconditional release from the party bringing such indemnified claims of all liability of the Indemnified Party or Indemnified Person in respect to or arising out of such claim or litigation in favor of, and (iii) does not include any admission of fault, culpability, wrongdoing, or wrongdoing or malfeasance by or on behalf of, the Indemnified Party or Indemnified Person. Following indemnification as provided for hereunder, the indemnifying party shall be subrogated to all rights of the Indemnified Party or Indemnified Person with respect to all third parties, firms or corporations relating to the matter for which indemnification has been made. The failure to deliver written notice to the indemnifying party within a reasonable time of the commencement of any such action shall not relieve such indemnifying party of any liability to the Indemnified Person or Indemnified Party under this Section 6, except to the extent that the indemnifying party is prejudiced in its ability to defend such action.

(d)            The indemnification required by this Section 6 shall be made by periodic payments of the amount thereof during the course of the investigation or defense, as and when bills are received or Indemnified Damages are incurred. Any Person receiving a payment pursuant to this Section 6 which person is later determined to not be entitled to such payment shall return such payment (including reimbursement of expenses) to the person making it.

(e)            The indemnity agreements contained herein shall be in addition to (i) any cause of action or similar right of the Indemnified Party or Indemnified Person against the indemnifying party or others, and (ii) any liabilities the indemnifying party may be subject to pursuant to the law.

CONTRIBUTION.

To the extent any indemnification by an indemnifying party is prohibited or limited by law, the indemnifying party agrees to make the maximum contribution with respect to any amounts for which it would otherwise be liable under Section 6 to the fullest extent permitted by law; provided, however, that: (i) no seller of Registrable Securities guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any seller of Registrable Securities who was not guilty of fraudulent misrepresentation; and (ii) contribution by any seller of Registrable Securities shall be limited in amount to the net amount of proceeds (net of all expenses paid by such holder in connection with any claim relating to this Section 7 and the amount of any damages such holder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission) received by such seller from the sale of such Registrable Securities giving rise to such contribution obligation.

ASSIGNMENT OF REGISTRATION RIGHTS.

The Company shall not assign this Agreement or any rights or obligations hereunder (whether by operation of law or otherwise) without the prior written consent of the Required Investors; provided, however, that in any transaction, whether by merger, reorganization, restructuring, consolidation, financing or otherwise, whereby the Company is a party and in which the Registrable Securities are converted into the equity securities of another Person, from and after the effective time of such transaction, such Person shall, by virtue of such transaction, be deemed to have assumed the obligations of the Company hereunder, the term “Company” shall be deemed to refer to such Person and the term “Registrable Securities” shall be deemed to include the securities received by the Investor in connection with such transaction unless such securities are otherwise freely tradable by the Investor after giving effect to such transaction, and the prior written consent of the Required Investors shall not be required for such transaction.

An Investor may transfer or assign its rights hereunder, in whole or from time to time in part, to one or more Persons in connection with the transfer of Registrable Securities (including Registrable Securities issuable upon exercise of Warrants) by such Investor to such Person, provided that such Investor complies with all laws applicable thereto, and the provisions of the Purchase Agreement, and provides written notice of assignment to the Company promptly after such assignment is effected, and such Person agrees in writing to be bound by all of the provisions contained herein.

The provisions of this Agreement shall be binding upon and inure to the benefit of the Investor and its successors and permitted assigns.

AMENDMENTS AND WAIVERS.

The provisions of this Agreement, including the provisions of this sentence, may be amended, modified or supplemented, or waived only by a written instrument executed by (i) the Company and (ii) the Required Investors, provided that (1) any party may give a waiver as to itself, (2) any amendment, modification, supplement or waiver that disproportionately and adversely affects the rights and obligations of any Investor relative to the comparable rights and obligations of the other Investors shall require the prior written consent of such adversely affected Investor or each Investor, as applicable, and (3) any amendments to Section 6 or to the definitions of “Filing Deadline,” “Effectiveness Deadline,” or “Registration Period” shall require the written consent of each Investor. Notwithstanding the foregoing, a waiver or consent to depart from the provisions hereof with respect to a matter that relates exclusively to the rights of one or more Investors and that does not adversely directly or indirectly affect the rights of other Investors may be given by Investors holding all of the Registrable Securities to which such waiver or consent relates.

10.

MISCELLANEOUS.

(a)            Notices. Any notices or other communications required or permitted to be given hereunder shall be in writing and shall be deemed to be given (a) when delivered if personally delivered to the party for whom it is intended, (b) when delivered, if sent by electronic mail during normal business hours of the recipient, and if not sent during normal business hours, then on the recipient’s next business day, (c) three days after having been sent by certified or registered mail, return-receipt requested and postage prepaid, or (d) one business day after deposit with a nationally recognized overnight courier, freight prepaid, specifying next business day delivery, with written verification of receipt:

i.            If to the Company, addressed as follows:

Zenas BioPharma, Inc.

852 Winter Street, Suite 250

Waltham, MA 02451
Attention: Jeff Held, Chief Legal Officer

Email: jeff.held@zenasbio.com

with a copy (which shall not constitute notice):

Ropes & Gray LLP

Prudential Tower

800 Boylston Street

Boston, MA 02199
Attention: Thomas Danielski
Email: thomas.danielski@ropesgray.com

ii.            If to any Investor, at its e-mail address or address set forth on its signature page to the Purchase Agreement or to such e-mail address, or address as subsequently modified by written notice given in accordance with this Section 10.

Any Person may change the address to which notices and communications to it are to be addressed by notification as provided for herein.

(b)            Consent to Electronic Notice. Each Investor consents to the delivery of any stockholder notice pursuant to this Agreement at the e-mail address set forth below the Investor’s name on its signature page to the Purchase Agreement, as updated from time to time by notice to the Company. To the extent that any notice given by means of electronic mail is returned or undeliverable for any reason, the foregoing consent shall be deemed to have been revoked until a new or corrected e-mail address has been provided, and such attempted electronic notice shall be ineffective and deemed to not have been given. Each party agrees to promptly notify the other parties of any change in its e-mail address, and that failure to do so shall not affect the foregoing.

(c)            Waiver. No waiver of any term, provision or condition of this Agreement, whether by conduct or otherwise, in any one or more instances, shall be deemed to be, or be construed as, a further or continuing waiver of any such term, provision or condition or as a waiver of any other term, provision or condition of this Agreement.

(d)            Governing Law. The provisions of Section 8.6 of the Purchase Agreement are incorporated by reference herein mutatis mutandis.

(e)            Headings. The titles, subtitles and headings in this Agreement are for convenience of reference and shall not form part of, or affect the interpretation of, this Agreement.

(f)            Counterparts. This Agreement may be executed in two or more identical counterparts, all of which shall be considered one and the same agreement and shall become effective when counterparts have been signed by each party and delivered to the other party; provided that a facsimile or pdf signature including any electronic signatures complying with the U.S. federal ESIGN Act of 2000, e.g., www.docusign.com shall be considered due execution and shall be binding upon the signatory thereto with the same force and effect as if the signature were an original, not a facsimile or pdf (or other electronic reproduction of a) signature.

(g)            Further Assurances. Each party shall do and perform, or cause to be done and performed, all such further acts and things, and shall execute and deliver all such other agreements, certificates, instruments and documents as the other party may reasonably request in order to carry out the intent and accomplish the purposes of this Agreement and the consummation of the transactions contemplated hereby.

(h)            Contract Interpretation. This Agreement is the joint product of each Investor and the Company and each provision hereof has been subject to the mutual consultation, negotiation and agreement of such parties and shall not be construed for or against any party hereto.

(i)            No Third Party Beneficiaries. Nothing in this Agreement, express or implied, is intended to confer on any Person other than the parties to this Agreement any rights, remedies, claims, benefits, obligations or liabilities under or by reason of this Agreement, and no Person that is not a party to this Agreement (including, without limitation, any partner, member, shareholder, director, officer, employee or other beneficial owner of any party to this Agreement, in its own capacity as such or in bringing a derivative action on behalf of a party to this Agreement) shall have any standing as a third party beneficiary with respect to this Agreement or the transactions contemplated hereby.

(j)            Severability. If any part or provision of this Agreement is held unenforceable or in conflict with the applicable laws or regulations of any jurisdiction, the invalid or unenforceable part or provisions shall be replaced with a provision which accomplishes, to the extent possible, the original business purpose of such part or provision in a valid and enforceable manner, and the remainder of this Agreement shall remain binding upon the parties hereto.

(k)            Non-Recourse. Notwithstanding anything that may be expressed or implied in this Agreement, the Company covenants, agrees and acknowledges that no recourse under this Agreement or any documents or instruments delivered in connection with this Agreement shall be had against any current or future director, officer, employee, stockholder, general or limited partner or member of the Investors or of any affiliates or assignees thereof, whether by the enforcement of any assessment or by any legal or equitable proceeding, or by virtue of any statute, regulation or other applicable law, it being expressly agreed and acknowledged that no personal liability whatsoever shall attach to, be imposed on or otherwise be incurred by any current or future director, officer, employee, stockholder, general or limited partner or member of the Investors or of any affiliates or assignees thereof, as such for any obligation of the Investors under this Agreement or any documents or instruments delivered in connection with this Agreement for any claim based on, in respect of or by reason of such obligations or their creation.

(l)            Specific Performance. In addition to any and all other remedies that may be available at law in the event of any breach of this Agreement, each Investor shall be entitled to specific performance of the agreements and obligations of the Company hereunder and to such other injunction or other equitable relief as may be granted by a court of competent jurisdiction.

(m)            Cumulative Remedies. The remedies provided herein are cumulative and not exclusive of any remedies provided by law.

[Signature Page Follows]

IN WITNESS WHEREOF, the parties have caused this Registration Rights Agreement to be duly executed as of date first written above.

	COMPANY:

	ZENAS BIOPHARMA, INC.

	By:
		Name:
		Title:

[Signature Page to Registration Rights Agreement]

IN WITNESS WHEREOF, the parties have caused this Registration Rights Agreement to be duly executed as of date first written above.

	INVESTOR:

	[NAME]

	By:
	Name:
	Title:

[Signature Page to Registration Rights Agreement]

Exhibit A

PLAN OF DISTRIBUTION

The selling stockholders, which as used herein includes donees, pledgees, transferees or other successors-in-interest selling shares of common stock or interests in shares of common stock received after the date of this prospectus from a selling stockholder as a gift, pledge, partnership distribution or other transfer, may, from time to time, sell, transfer or otherwise dispose of any or all of their shares of common stock or interests in shares of common stock on any stock exchange, market or trading facility on which the shares are traded or in private transactions. These dispositions may be at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, at varying prices determined at the time of sale, or at negotiated prices.

The selling stockholders may use any one or more of the following methods when disposing of shares or interests therein:

•

distributions to members, partners, stockholders or other equityholders of the selling stockholders;

•

ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;

•

block trades in which the broker-dealer will attempt to sell the shares as agent, but may position and resell a portion of the block as principal to facilitate the transaction;

•

purchases by a broker-dealer as principal and resale by the broker-dealer for its account;

•

an exchange distribution in accordance with the rules of the applicable exchange;

•

privately negotiated transactions;

•

short sales and settlement of short sales entered into after the effective date of the registration statement of which this prospectus is a part;

•

through the writing or settlement of options or other hedging transactions, whether through an options exchange or otherwise;

•

broker-dealers may agree with the selling stockholders to sell a specified number of such shares at a stipulated price per share;

•

a combination of any such methods of sale; and

•

any other method permitted pursuant to applicable law.

The selling stockholders may, from time to time, pledge or grant a security interest in some or all of the shares of common stock owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the shares of common stock, from time to time, under this prospectus, or under an amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the Securities Act, amending the list of selling stockholders to include the pledgee, transferee or other successors in interest as selling stockholders under this prospectus. The selling stockholders also may transfer the shares of common stock in other circumstances, in which case the transferees, pledgees or other successors in interest will be the selling stockholders for purposes of this prospectus.

In connection with the sale of our common stock or interests therein, the selling stockholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the common stock in the course of hedging the positions they assume. The selling stockholders may also sell shares of our common stock short and deliver these securities to close out their short positions, or loan or pledge the common stock to broker-dealers that in turn may sell these securities. The selling stockholders may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of shares offered by this prospectus, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

The aggregate proceeds to the selling stockholders from the sale of the common stock offered by them will be the purchase price of the common stock less discounts or commissions, if any. Each of the selling stockholders reserves the right to accept and, together with their agents from time to time, to reject, in whole or in part, any proposed purchase of common stock to be made directly or through agents. We will not receive any of the proceeds from this offering.

The selling stockholders also may resell all or a portion of the shares in open market transactions in reliance upon Rule 144 under the Securities Act, provided that they meet the criteria and conform to the requirements of that rule, or another available exemption from the registration requirements under the Securities Act.

The selling stockholders and any underwriters, broker-dealers or agents that participate in the sale of the common stock or interests therein may be “underwriters” within the meaning of Section 2(a)(11) of the Securities Act (it being understood that the selling stockholders shall not be deemed to be underwriters solely as a result of their participation in this offering). Any discounts, commissions, concessions or profit they earn on any resale of the shares may be underwriting discounts and commissions under the Securities Act. Selling stockholders who are “underwriters” within the meaning of Section 2(a)(11) of the Securities Act will be subject to the prospectus delivery requirements of the Securities Act.

To the extent required, the shares of our common stock to be sold, the names of the selling stockholders, the respective purchase prices and public offering prices, the names of any agent, dealer or underwriter, and any applicable commissions or discounts with respect to a particular offer will be set forth in an accompanying prospectus supplement or, if appropriate, a post-effective amendment to the registration statement that includes this prospectus.

In order to comply with the securities laws of some states, if applicable, the common stock may be sold in these jurisdictions only through registered or licensed brokers or dealers. In addition, in some states the common stock may not be sold unless it has been registered or qualified for sale or an exemption from registration or qualification requirements is available and is complied with.

We have advised the selling stockholders that the anti-manipulation rules of Regulation M under the Exchange Act may apply to sales of shares in the market and to the activities of the selling stockholders and their affiliates. In addition, to the extent applicable, we will make copies of this prospectus (as it may be supplemented or amended from time to time) available to the selling stockholders for the purpose of satisfying the prospectus delivery requirements of the Securities Act. The selling stockholders may indemnify any broker-dealer that participates in transactions involving the sale of the shares against certain liabilities, including liabilities arising under the Securities Act.

We have agreed to indemnify the selling stockholders against liabilities, including liabilities under the Securities Act and state securities laws, relating to the registration of the shares offered by this prospectus.

We have agreed with the selling stockholders to use commercially reasonable efforts to cause the registration statement of which this prospectus constitutes a part to become effective and to remain continuously effective until the earlier of: (i) the date on which the selling stockholders shall have resold or otherwise disposed of all the shares covered by this prospectus and (ii) the date on which the shares covered by this prospectus no longer constitute “Registrable Securities” as such term is defined in the Registration Rights Agreement, such that they may be resold by the selling stockholders without registration and without regard to any volume or manner-of-sale limitations and without current public information pursuant to Rule 144 under the Securities Act or any other rule of similar effect.

Exhibit B

Investor Questionnaire

The undersigned hereby provides the following information to the Company and represents and warrants that such information is accurate:

QUESTIONNAIRE

Name.

(a)

Full Legal Name of Investor

(b)

Full Legal Name of Registered Holder (if not the same as (a) above) through which Registrable Securities are held:

(c)

Full Legal Name of Natural Control Person (which means a natural person who directly or indirectly alone or with others has power to vote or dispose of the securities covered by this Questionnaire):

2. Address for Notices to Investor:

Telephone:
E-Mail:
Contact Person:

3. Broker-Dealer Status:

(a)

Are you a broker-dealer?

Yes ¨             No ¨

(b)

If “yes” to Section 3(a), did you receive your Registrable Securities as compensation for investment banking services to the Company?

Yes ¨             No ¨

Note:

If “no” to Section 3(b), the Commission’s staff has indicated that you should be identified as an underwriter in the Registration Statement.

(c)

Are you an affiliate of a broker-dealer?

Yes ¨             No ¨

(d)

If you are an affiliate of a broker-dealer, do you certify that you purchased the Registrable Securities in the ordinary course of business, and at the time of the purchase of the Registrable Securities to be resold, you had no agreements or understandings, directly or indirectly, with any person to distribute the Registrable Securities?

Yes ¨             No ¨

Note:

If “no” to Section 3(d), the Commission’s staff has indicated that you should be identified as an underwriter in the Registration Statement.

4. Beneficial Ownership of Securities of the Company Owned by the Investor.

Except as set forth below in this Item 4, the undersigned is not the beneficial or registered owner of any securities of the Company other than the securities issuable pursuant to the Purchase Agreement.

(a)

Type and Amount of other securities beneficially owned by the Investor:

5. Relationships with the Company:

Except as set forth below, neither the undersigned nor any of its affiliates, officers, directors or principal equity holders (owners of 5% of more of the equity securities of the undersigned) has held any position or office or has had any other material relationship with the Company (or its predecessors or affiliates) during the past three years.

State any exceptions here:

The undersigned agrees to promptly notify the Company of any material inaccuracies or changes in the information provided herein that may occur subsequent to the date hereof at any time while the Registration Statement remains effective; provided, that the undersigned shall not be required to notify the Company of any changes to the number of securities held or owned by the undersigned or its affiliates.

By signing below, the undersigned consents to the disclosure of the information contained herein in its answers to Items 1 through 5 and the inclusion of such information in the Registration Statement and the related prospectus and any amendments or supplements thereto. The undersigned understands that such information will be relied upon by the Company in connection with the preparation or amendment of the Registration Statement and the related prospectus and any amendments or supplements thereto.

IN WITNESS WHEREOF the undersigned, by authority duly given, has caused this Notice and Questionnaire to be executed and delivered either in person or by its duly authorized agent.

Date:

Beneficial Owner:

	By:
	Name:
	Title:

PLEASE EMAIL A .PDF COPY OF THE COMPLETED AND EXECUTED QUESTIONNAIRE TO: chase.jayasekera@zenasbio.com

Zenas BioPharma, Inc. 8-K