Exhibit
4.4


 


Sera
Prognostics, Inc.





Public
Offering of Common Stock


 


,
2021


 


Citigroup
Global Markets Inc.


Cowen
and Company, LLC


William
Blair & Company, L.L.C.


  As
Representatives of the several Underwriters


 


c/o
Citigroup Global Markets Inc.


388
Greenwich Street


New
York, New York 10013


 


c/o
Cowen and Company, LLC


599
Lexington Avenue


New
York, New York 10022


 


c/o
William Blair & Company, L.L.C.


150
North Riverside Plaza


Chicago,
Illinois 60606


 


Ladies
and Gentlemen:


 


This
letter is being delivered to you in connection with the proposed underwriting agreement (the “Underwriting Agreement”),
between Sera Prognostics, Inc., a Delaware corporation (the “Company”), and each of you as representatives (the “Representatives”)
of a group of Underwriters named therein, relating to an underwritten public offering of Common Stock, $0.0001 par value (the “Common
Stock”), of the Company (the “Offering”).


 


In
order to induce you and the other Underwriters to enter into the Underwriting Agreement, the undersigned will not, without the prior
written consent of the Representatives, offer, sell, contract to sell, pledge or otherwise dispose of (or enter into any transaction
which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective
economic disposition due to cash settlement or otherwise) by the undersigned or any affiliate of the undersigned or any person in
privity with the undersigned or any affiliate of the undersigned), directly or indirectly, including the filing (or participation in
the filing) of a registration statement with the U.S. Securities and Exchange Commission (“SEC”) in respect of,
or establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section
16 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the rules and regulations of the
SEC promulgated thereunder with respect to, any shares of capital stock of the Company or any securities convertible into, or
exercisable or exchangeable for such capital stock, or publicly announce an intention to effect any such transaction, for a period
from the date hereof until 180 days after the date of the Underwriting Agreement (the “Restricted Period”). If the
undersigned is an officer or director of the Company, the
undersigned further agrees that the foregoing restrictions shall be equally applicable to any issuer-directed shares of Common Stock
the undersigned may purchase in the Offering.


 






    1


     


    

 


The
provisions of the immediately preceding paragraph shall not apply to or prohibit any of the following:


 


		(i)	transfers
                                            of shares of capital stock of the Company or any securities convertible into or exercisable
                                            or exchangeable for such capital stock as a bona fide gift or gifts;



 


		(ii)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock to any trust for the direct or indirect
                                            benefit of the undersigned or the immediate family of the undersigned or if the undersigned
                                            is a trust, to a trustor or beneficiary of the trust or to the estate of the beneficiary
                                            of such trust, in each case, in a transaction not involving a disposition for value;



 


		(iii)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock to any corporation, partnership, limited
                                            liability company or other entity, all of the beneficial ownership interests of which are
                                            held by the undersigned or the immediate family of the undersigned, in a transaction not
                                            involving a disposition for value;



 


		(iv)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock by will, other testamentary document
                                            or intestate succession to the legal representative, heir, beneficiary or a member of the
                                            immediate family of the undersigned; provided that if a filing pursuant to Section 16(a)
                                            of the Exchange Act is required in connection with such transfer or disposition, such filing
                                            shall describe the nature of the transfer;



 


		(v)	distributions
                                            of shares of capital stock of the Company or any securities convertible into or exercisable
                                            or exchangeable for such capital stock to partners, members or stockholders of the undersigned;



 


		(vi)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock pursuant to a bona fide third-party
                                            tender offer, merger, consolidation, business combination, stock purchase or other similar
                                            transaction or series of related transactions approved by the board of directors of the Company
                                            and made to all holders of the Company’s capital stock involving a Change in Control
                                            (defined herein), provided that in the event that such tender offer, merger, consolidation,
                                            business combination, stock purchase or similar transaction or series of related transactions
                                            is not completed, the shares of capital stock of the Company or any securities convertible
                                            into or exercisable or exchangeable for such capital stock held by the undersigned shall
                                            remain subject to the restrictions set forth herein;









 






    2


     


    

 


		(vii)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock by operation of law, such as pursuant
                                            to a qualified domestic order, divorce settlement, divorce decree, separation agreement or
                                            court order; provided that if a filing pursuant to Section 16(a) of the Exchange Act is required
                                            in connection with such transfer or disposition, such filing shall describe the nature of
                                            the transfer;



 


		(viii)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock to the undersigned’s affiliates
                                            or to any investment fund or other entity controlled or managed by the undersigned;



 


		(ix)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock pursuant to any contractual arrangement
                                            described in the final prospectus relating to the Offering (the “Prospectus”)
                                            that provides for the repurchase by the Company of securities of the Company held by the
                                            undersigned in connection with the termination of the undersigned’s employment with,
                                            or service to, the Company; provided that if a filing pursuant to Section 16(a) of the Exchange
                                            Act is required in connection with such transfer or disposition, such filing shall describe
                                            the nature of the transfer; and



 


		(x)	transfers
                                            or dispositions of shares of capital stock of the Company or any securities convertible into
                                            or exercisable or exchangeable for such capital stock by surrender or forfeiture of shares
                                            of Common Stock or other securities of the Company to the Company to satisfy tax withholding
                                            obligations upon exercise or vesting or the exercise price upon a cashless net exercise,
                                            in each case, of stock options, restricted stock, other equity awards, warrants or other
                                            rights to acquire shares of Common Stock as described in the Prospectus; provided that if
                                            a filing pursuant to Section 16(a) of the Exchange Act is required in connection with such
                                            transfer or disposition, such filing shall describe the nature of the transfer;



 


provided,
that in the case of any transfer, disposition or distribution pursuant to clause (i), (ii), (iii), (iv), (v), (vii) or (viii), each transferee,
donee or distributee shall execute and deliver to the Representatives a lock-up letter in the form of this letter; and provided further
that, in the case of any transfer, disposition or distribution pursuant to clause (i), (ii), (iii), (v) or (viii), no filing by any
party (donor, donee, transferor or transferee) under the Exchange Act or other public announcement reporting a reduction in the beneficial
ownership of Common Stock held by the undersigned shall be required or shall be made voluntarily in connection with such transfer, disposition
or distribution (other than a filing on a Form 5 or Schedule 13F made after the expiration of the restrictions set forth herein). For
purposes of this letter, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than
first cousin, and “Change in Control” shall mean the transfer (whether by tender offer, merger, consolidation or other similar
transaction), in one transaction or a series of related transactions, in each case occurring subsequent to the Offering, to a person
or group of affiliated persons (other than an Underwriter pursuant to the Offering), of the Company’s voting securities if, after
such transfer, such
person or group of affiliated persons would hold more than 50% of the outstanding voting securities of the Company (or the surviving
entity).


 






    3


     


    

 


Notwithstanding
the restrictions imposed by this letter, the undersigned may, without the prior written consent of the Representatives, (a) exercise
an option to purchase shares of Common Stock granted under any stock incentive plan or stock purchase plan of the Company or
exercise outstanding warrants to purchase shares of the Company’s capital stock, provided that the underlying shares
issuable upon exercise thereof shall continue to be subject to the restrictions on transfer set forth in this letter, (b) establish
a trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of Common Stock, provided that such
plan does not provide for any transfers of Common Stock, and no filing with the SEC or other public announcement shall be required
or voluntarily made by the undersigned or any other person in connection therewith, in each case during the period that the
restrictions set forth herein are in effect, (c) transfer or dispose of shares of Common Stock purchased in the Offering from the
Underwriters (other than any issuer-directed shares of Common Stock purchased in the Offering by an officer or director of the
Company) or on the open market following the Offering and (d) convert outstanding
shares of preferred stock, warrants to acquire preferred stock or convertible securities or warrants to acquire shares of Common
Stock into shares of Common Stock; provided that any such shares of Common Stock or warrants received upon such conversion
shall be subject to the restrictions on transfer set forth in this letter.


 


If
the undersigned is an officer or director of the Company, (i) the Representatives agree that, at least three business days before the
effective date of any release or waiver of the foregoing restrictions in connection with a transfer of shares of Common Stock, the Representatives
will notify the Company of the impending release or waiver, and (ii) the Company has agreed in the Underwriting Agreement to announce
the impending release or waiver by press release through a major news service at least two business days before the effective date of
the release or waiver. Any release or waiver granted by the Representatives hereunder to any such officer or director shall only be effective
two business days after the publication date of such press release. The provisions of this paragraph will not apply if (a) the release
or waiver is effected solely to permit a transfer not for consideration and (b) the transferee has agreed in writing to be bound by the
same terms described in this letter to the extent and for the duration that such terms remain in effect at the time of the transfer.


 






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In
the event that, during the Restricted Period, the Representatives agree to an Exception (as defined below), the Representatives
shall be deemed to have also granted the same Exception with respect to the prohibitions set forth in this agreement that would
otherwise have applied to the undersigned with respect to the same percentage of the undersigned’s shares of Common Stock as
the relative percentage of aggregate shares held by such party benefitting from the Exception that are being transferred pursuant to
such Exception. The provisions of this paragraph will not apply unless and until the Representatives have granted an Exception with
respect to more than 1.5%, in the aggregate (or more than 1% of outstanding shares of Common Stock with respect to any individual
holder), of outstanding shares of Common Stock subject to this agreement or a similar letter agreement, provided, however, that this
1.5% “de minimis” exception shall not apply to an Exception granted to a director or officer of the Company (and for the
avoidance of doubt, an Exception granted to a director or officer of the Company would cause an Exception to be automatically
granted with respect to the undersigned’s shares of Common Stock in accordance with the first sentence hereof) unless
such waiver is granted due to financial hardship as reasonably determined by the Representatives or if the Exception is effective
solely to permit a transfer not involving a disposition for value if the transferee agrees in writing to be bound by the same terms
described in this Agreement. Furthermore, if the release, in full or in part, of any shares of Common Stock from the restrictions of
this agreement is in connection with an underwritten follow-on offering that includes such released shares (a “Follow-On
Offering”), then the shares of Common Stock held by the undersigned shall be released only to the extent that the undersigned
has a contractual right to demand or require the registration of the undersigned’s Common Stock or otherwise
“piggyback” on a registration statement filed by the Company in connection with the Follow-On Offering, and the
undersigned agrees to participate as a selling stockholder in the Follow-On Offering and to sell any of the shares of Common Stock
released from the restrictions of this agreement in such Follow-On Offering, provided that the undersigned enters into a new lock-up
letter with the underwriters with respect to the shares of Common Stock that are not being released, upon terms and conditions
reasonably satisfactory to the underwriters but with restrictions that will be no more restrictive than those set forth herein
(other than that the expiration of the new lock-up shall be until the later of the Restricted Period hereunder or 90 days from the
date of such Follow-On Offering). In the event that, as a result of this paragraph, any of the undersigned’s shares of Common
Stock are released from the restrictions imposed by this agreement, the Company shall use its commercially reasonable efforts to
notify the undersigned within three business days after the Company has been advised by the Representatives of such release that the
same percentage of shares of Common Stock held by the undersigned has been released, provided that the failure to give such notice
shall not give rise to any claim or liability against the Company or the underwriters. For purposes of this Letter Agreement, an
“Exception” shall mean any release or waiver (no matter how effectuated, including through an amendment, a new agreement
or otherwise) by the Representatives during the Restricted Period of any prohibition set forth in this Letter Agreement or a similar
letter agreement on the disposition or transfer of Common Stock held by any person or entity that beneficially owns 1% or more of
the outstanding shares of Common Stock (each, a “Significant Holder”), any director of the Company or any officer of the
Company.


 






    5


     


    

 


This
letter shall automatically terminate and the undersigned shall be released from all obligations under this letter upon the earliest to
occur, if any, of (i) either the Company, on the one hand, or the Representatives, on the other hand, advising the other in writing,
prior to the execution of the Underwriting Agreement, that they have determined not to proceed with the Offering, (ii) the Underwriting
Agreement being terminated prior to the Closing Date (as defined in the Underwriting Agreement), (iii) the registration statement filed
with the SEC with respect to the Offering being withdrawn and (iv) September 30, 2021 in the event that the Underwriting Agreement has
not been executed by such date.


 


This
letter and any claim, controversy or dispute arising under or related to this letter will be governed by and construed in accordance
with the laws of the State of New York applicable to contracts made and to be performed within the State of New York.


 


The
undersigned understands that the Company and the Underwriters are relying upon this letter agreement in proceeding toward
consummation of the Offering. The undersigned further understands that this letter agreement is irrevocable and shall be binding
upon the undersigned’s heirs, legal representatives, successors, and assigns. This letter agreement may be delivered via facsimile,
electronic mail (including pdf or any electronic signature complying with the U.S. federal ESIGN Act of 2000, e.g., www.docusign.com
or www.echosign.com) or other transmission method and any counterpart so delivered shall be deemed to have been duly and validly
delivered and be valid and effective for all purposes.


 





	 	Yours very truly, 
	 	 
	 	By:	/s/ Marcin Czernik
	 	Name: 	Marcin Czernik
	 	Title:	Director, Chione Limited


 


 


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