Sec Form 4 Filing - Mento Steven J @ Histogen Inc. - 2021-11-08

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Mento Steven J 2. Issuer Name and Ticker or Trading Symbol Histogen Inc. [ HSTO] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Interim President and CEO (Last) (First) (Middle) C/O HISTOGEN INC., 10655 SORRENTO VALLEY ROAD, SUITE 200 3. Date of Earliest Transaction (MM/DD/YY) 11/08/2021 (Street) SAN DIEGO, CA92121 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Stock Option (right to buy) $ 0.729 11/08/2021 A 377,830 ( 1 ) 11/08/2031 Common Stock 377,830 $ 0 377,830 D Restricted Stock Unit ( 2 ) 11/08/2021 A 228,395 ( 3 ) 11/08/2031 Common Stock 228,395 $ 0 228,395 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Mento Steven J C/O HISTOGEN INC. 10655 SORRENTO VALLEY ROAD, SUITE 200 SAN DIEGO, CA92121 X Interim President and CEO Signatures /s/ Susan A. Knudson as attorney-in-fact for Steven J. Mento, Ph.D. 11/10/2021 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Twenty-five percent (25%) of the option award shall vest on the annual anniversary of the option award so that one hundred percent (100%) of the option award shall vest by the fourth anniversary of the grant date, subject to the Reporting Person continuing to provide services to Issuer through the relevant vesting dates. ( 2 )Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock. ( 3 )One hundred percent of the restricted stock units will vest upon the earlier to occur of (i) one (1) year after the grant date, or (ii) the Issuer's hiring of a permanent Chief Executive Officer and President, subject to the Reporting Person's continuing to provide services to Issuer through the relevant vesting dates.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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