MBIO Mustang Bio Inc

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 * Achenbach Brian	2. Issuer Name and Ticker or Trading Symbol MUSTANG BIO, INC. [ MBIO ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) SVP, Fin. & Corp. Controller
(Last)          (First)          (Middle) 377 PLANTATION STREET	3. Date of Earliest Transaction (MM/DD/YYYY) 12/6/2019
(Street) WORCESTER, MA 01605 (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	12/6/2019		S(1)		6144	D	$3.69 (7)	145630 (8)	D
COMMON STOCK	3/31/2020		S(2)		3033	D	$2.64 (7)	142597 (8)	D
COMMON STOCK	5/22/2020		S(3)		880	D	$3.04 (7)	141717 (8)	D
COMMON STOCK	10/21/2020		S(4)		3056	D	$2.97 (7)	138661 (8)	D
COMMON STOCK	12/8/2020		S(5)		5185	D	$3.03 (7)	133476 (8)	D
COMMON STOCK	4/9/2021		S(6)		2423	D	$3.36 (7)	131053 (8)	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

Explanation of Responses:
(1)	6,144 shares were sold in connection with the vesting of 13,750 shares on December 4, 2019, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(2)	3,033 shares were sold in connection with the vesting of 8,750 shares on March 27, 2020, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(3)	880 shares were sold in connection with the vesting of 3,438 shares on March 26, 2020, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(4)	3,056 shares were sold in connection with the vesting of 9,063 shares on October 10, 2020, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(5)	5,185 shares were sold in connection with the vesting of 13,750 shares on December 4, 2020, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(6)	2,423 shares were sold in connection with the vesting of 8,750 shares on March 27, 2021, these shares were sold by the Company's restricted stock administrator in order to satisfy Mr. Achenbach's tax withholding obligations. Mr. Achenbach had no discretion with respect to such sale, which was transacted automatically in accordance with the Company's corporate policies regarding the vesting of restricted stock.
(7)	Represents the weighted average sales price.
(8)	Includes restricted share units, which vest over various time periods.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Achenbach Brian 377 PLANTATION STREET WORCESTER, MA 01605			SVP, Fin. & Corp. Controller

Signatures
/s/ Brian Achenbach		4/16/2021
**Signature of Reporting Person		Date