Sec Form 4 Filing - GIANAKAKOS ANASTASIOS @ MyoKardia, Inc. - 2020-05-11

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 GIANAKAKOS ANASTASIOS 2. Issuer Name and Ticker or Trading Symbol MyoKardia, Inc. [ MYOK] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) President and CEO (Last) (First) (Middle) C/O MYOKARDIA, INC., 1000 SIERRA POINT PARKWAY 3. Date of Earliest Transaction (MM/DD/YY) 05/11/2020 (Street) BRISBANE, CA94005 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 Common Stock 05/11/2020 S( 1 ) 600 D $ 98.6883 ( 2 ) 63,522 ( 3 ) D Common Stock 05/11/2020 S( 1 ) 1,700 D $ 100.5056 ( 4 ) 61,822 D Common Stock 05/11/2020 S( 1 ) 18,581 D $ 101.9044 ( 5 ) 43,241 D Common Stock 05/11/2020 S( 1 ) 3,519 D $ 102.5635 ( 6 ) 39,722 D Common Stock 05/11/2020 S( 1 ) 600 D $ 103.33 ( 7 ) 39,122 D Common Stock 129,407 I By Reporting Person's Trust 2 ( 8 ) Common Stock 300,000 I By Reporting Person's Trust 4 Common Stock 7,000 ( 9 ) I By Reporting Person's Trust 5 Common Stock 10,000 ( 10 ) I By Reporting Person's Trust 6 Common Stock 53,087 I By Trust 1 Common Stock 53,087 I By Trust 2 Common Stock 53,087 I By Trust 3

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

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other GIANAKAKOS ANASTASIOS C/O MYOKARDIA, INC. 1000 SIERRA POINT PARKWAY BRISBANE, CA94005 X President and CEO Signatures /s/ Cynthia Ladd, as Attorney-in-Fact 05/13/2020 Signature of Reporting Person Date

Explanation of Responses:

( 1 )This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person. ( 2 )Represents the weighted average sale price of the shares sold ranging from $98.50 to $99.46 per share. The Reporting Person will provide, upon request by the Commission staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares sold at each separate price within the ranges reported in this footnote and footnotes 4 through 7. ( 3 )Excludes 10,000 shares previously owned directly which were contributed on May 6, 2020 to the MJA Legacy Trust, of which the Reporting Person's children are beneficiaries. ( 4 )Represents the weighted average price of the shares sold ranging from $100.01 to $100.94 per share. ( 5 )Represents the weighted average price of the shares sold ranging from $101.07 to $102.05 per share. ( 6 )Represents the weighted average price of the shares sold ranging from $102.11 to $103.09 per share. ( 7 )Represents the weighted average price of the shares sold ranging from $103.19 to $103.54 per share. ( 8 )Excludes 1,000 shares previously held by The TKG Trust dated November 2, 2006 which were redistributed back to the Reporting Person directly and immediately transferred to The TKG 2020 Irrevocable Trust on May 5, 2020. ( 9 )Includes 1,000 shares previously held by The TKG Trust dated November 2, 2006 which were redistributed back to the Reporting Person directly and immediately transferred to The TKG 2020 Irrevocable Trust on May 5, 2020. ( 10 )Includes 10,000 shares previously owned directly which were contributed on May 6, 2020 to the MJA Legacy Trust, of which the Reporting Person's children are beneficiaries.

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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