MRIN Marin Software Incorporated

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 OF SECURITIES                                                                                   
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * Walcott Wister	2. Issuer Name and Ticker or Trading Symbol MARIN SOFTWARE INC [ MRIN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) EVP, Product and Technology
(Last)          (First)          (Middle) C/O MARIN SOFTWARE INCORPORATED, 123 MISSION ST, 27TH FLOOR	3. Date of Earliest Transaction (MM/DD/YYYY) 4/12/2021
(Street) SAN FRANCISCO, CA 94105 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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
Common Stock	4/12/2021		M		11250	A	(1)	100897	D
Common Stock	4/12/2021		F(2)		4622	D	$1.63	96275	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		7. Title and Amount of Securities Underlying Derivative Security (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
Restricted Stock Units (RSU)	(1)	4/12/2021		M			11250	(3)	4/12/2028	Common Stock	11250	$0.00	11250	D

Explanation of Responses:
(1)	Each restricted stock unit ("RSU") represents a contingent right to receive one (1) share of the Issuer's common stock upon settlement.
(2)	Exempt transaction pursuant to Section 16b-3(e) - payment of exercise price or tax liability by delivering or withholding securities incident to the receipt, exercise or vesting of a security issued in accordance with Rule 16b-3. All of the shares reported as disposed of in this Form 4 were relinquished by the Reporting Person and cancelled by the Issuer in exchange for the Issuer's agreement to pay federal and state tax withholding obligations of the Reporting Person resulting from the vesting of RSUs. The Reporting Person did not sell or otherwise dispose of any of the shares reported on this Form 4 for any reason other than to cover required taxes.
(3)	The shares of our common stock subject to the RSU award vest as to 25% of the shares subject to the RSU award on April 12, 2019 and the remaining shares subject to the RSU award vest annually thereafter over the next three years, such that the RSU award will be fully vested on April 12, 2022.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Walcott Wister C/O MARIN SOFTWARE INCORPORATED 123 MISSION ST, 27TH FLOOR SAN FRANCISCO, CA 94105			EVP, Product and Technology

Signatures
/s/ Wister Walcott by Robert Bertz, Attorney-in-Fact		4/14/2021
**Signature of Reporting Person		Date