Sec Form 3 Filing - BOBULSKY SUSAN @ Adaptive Biotechnologies Corp - 2024-01-25

FORM 3 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

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person BOBULSKY SUSAN 2. Issuer Name and Ticker or Trading Symbol Adaptive Biotechnologies Corp [ ADPT] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chief Commercial Officer, MRD (Last) (First) (Middle) C/O ADAPTIVE BIOTECHNOLOGIES CORPORATION, 1165 EASTLAKE AVENUE EAST 3. Date of Earliest Transaction (MM/DD/YY) 01/25/2024 (Street) SEATTLE, WA98109 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 128,302 D

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) $ 1.98 ( 1 ) 10/13/2024 Common Stock 5,000 D Stock Option (Right to Buy) $ 6.27 ( 1 ) 04/25/2027 Common Stock 20,000 D Stock Option (Right to Buy) $ 6.55 ( 1 ) 04/24/2028 Common Stock 28,750 D Stock Option (Right to Buy) $ 28.32 ( 2 ) 02/27/2030 Common Stock 13,474 D Stock Option (Right to Buy) $ 39.5 ( 3 ) 08/13/2030 Common Stock 20,000 D Stock Option (Right to Buy) $ 43.68 ( 4 ) 03/04/2031 Common Stock 22,894 D Stock Option (Right to Buy) $ 12.14 ( 5 ) 03/04/2032 Common Stock 102,965 D Stock Option (Right to Buy) $ 8.46 ( 6 ) 03/06/2033 Common Stock 88,689 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other BOBULSKY SUSAN C/O ADAPTIVE BIOTECHNOLOGIES CORPORATION 1165 EASTLAKE AVENUE EAST SEATTLE, WA98109 Chief Commercial Officer, MRD Signatures /s/ Susan Bobulsky by Stacy L. Taylor, Attorney-in-Fact 03/06/2024 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The options are fully exercisable. ( 2 )The options will vest with respect to 1/4 of such shares on February 27, 2021, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested. ( 3 )The options will vest with respect to 1/4 of such shares on August 6, 2021, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested. ( 4 )The options will vest with respect to 1/4 of such shares on March 4, 2022, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested. ( 5 )The options will vest with respect to 1/4 of such shares on March 4, 2023, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested. ( 6 )The options will vest with respect to 1/4 of such shares on March 4, 2024, with 1/48 of such shares vesting thereafter at the end of each full month of continuous service until fully vested.

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.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.