Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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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(Print or Type Responses)
1. Name and Address of Reporting Person *
  Wentworth Kerry
2. Date of Event Requiring Statement (Month/Day/Year)
12/21/2017
3. Issuer Name and Ticker or Trading Symbol
Flexion Therapeutics Inc [FLXN]
(Last)
(First)
(Middle)
C/O FLEXION THERAPEUTICS, INC., 10 MALL ROAD, SUITE 301
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Regulatory Officer
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

BURLINGTON, MA 01803
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 Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 5,077
D
 
Common Stock 6,000
I
By spouse

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy)   (1) 11/02/2024 Common Stock 24,000 $ 19.61 D  
Employee Stock Option (right to buy)   (2) 01/20/2025 Common Stock 10,000 $ 22.91 D  
Employee Stock Option (right to buy)   (3) 11/03/2025 Common Stock 10,000 $ 18.16 D  
Employee Stock Option (right to buy)   (4) 01/03/2026 Common Stock 20,000 $ 18.2 D  
Employee Stock Option (right to buy)   (5) 12/19/2026 Common Stock 35,000 $ 18.56 D  
Restricted Stock Unit Award   (6) 10/06/2019 Common Stock 6,800 $ (7) D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Wentworth Kerry
C/O FLEXION THERAPEUTICS, INC.
10 MALL ROAD, SUITE 301
BURLINGTON, MA 01803
      Chief Regulatory Officer  

Signatures

/s/ Mark S. Levine, Attorney-in-Fact 12/29/2017
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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).
(1) 1/4 of the shares subject to the option vest one year after November 3, 2014, with 1/48th of the shares vesting monthly thereafter over the next 3 years.
(2) 1/4 of the shares subject to the option vest one year after January 21, 2015, with 1/48th of the shares vesting monthly thereafter over the next 3 years.
(3) 1/4 of the shares subject to the option vest one year after November 4, 2015, with 1/48th of the shares vesting monthly thereafter over the next 3 years.
(4) 1/4 of the shares subject to the option vest one year after January 4, 2016, with 1/48th of the shares vesting monthly thereafter over the next 3 years.
(5) 1/4 of the shares subject to the option vest one year after December 20, 2016, with 1/48th of the shares vesting monthly thereafter over the next 3 years.
(6) 3,400 shares subject to the restricted stock unit award vest as of October 6, 2018 and the remaining 3,400 shares vest as of October 6, 2019.
(7) Each restricted stock unit award represents a contingent right to receive one share of the Issuer's common stock.

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