Adaptive Biotechnologies (ADPT) COO sells 57K shares under 10b5-1 plan

Rhea-AI Filing Summary

Adaptive Biotechnologies Corp President and COO Julie Rubinstein reported a series of option exercises and share sales in March 2026. She exercised stock options to acquire a total of 44,166 shares of common stock at exercise prices of $6.55 and $7.27 per share, then sold 57,180 shares in open-market transactions.

The sales occurred in three equal blocks of 19,060 shares at weighted average prices of $13.18, $13.37 and $13.83 per share. All transactions were carried out under a pre-arranged Rule 10b5-1 trading plan adopted on November 18, 2025. Following these trades, Rubinstein directly holds 481,906 shares of Adaptive Biotechnologies common stock.

Insights

Equity compensation and insider-trading analyst

Routine exercise-and-sell activity under a pre-planned Rule 10b5-1 trading plan.

President and COO Julie Rubinstein exercised options for 44,166 shares of Adaptive Biotechnologies common stock at strike prices of $6.55 and $7.27, then sold 57,180 shares in three open-market transactions at weighted average prices of $13.18, $13.37 and $13.83.

The filing notes these trades were made pursuant to a Rule 10b5-1 trading plan adopted on November 18, 2025, indicating the timing was pre-scheduled rather than discretionary. After the transactions, Rubinstein still directly owns 481,906 shares, suggesting she retains a substantial equity position in the company.

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

RUBINSTEIN JULIE

(Last) (First) (Middle)

C/O ADAPTIVE BIOTECHNOLOGIES CORPORATION

1165 EASTLAKE AVENUE EAST

(Street)

SEATTLE WASHINGTON 98109

(City) (State) (Zip)

UNITED STATES

(Country)

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)
	President and COO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/19/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	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	03/19/2026		M(1)		14,722	A	$6.55	509,642	D
Common Stock	03/19/2026		S(1)		19,060	D	$13.18(2)	490,582	D
Common Stock	03/20/2026		M(1)		3,939	A	$6.55	494,521	D
Common Stock	03/20/2026		M(1)		10,783	A	$7.27	505,304	D
Common Stock	03/20/2026		S(1)		19,060	D	$13.37(3)	486,244	D
Common Stock	03/23/2026		M(1)		14,722	A	$7.27	500,966	D
Common Stock	03/23/2026		S(1)		19,060	D	$13.83(4)	481,906	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 (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	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 (Month/Day/Year)		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: 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)	$6.55	03/19/2026		M(1)			14,722	(5)	02/07/2028	Common Stock	14,722	$0	3,939	D
Stock Option (right to buy)	$6.55	03/20/2026		M(1)			3,939	(5)	02/07/2028	Common Stock	3,939	$0	0	D
Stock Option (right to buy)	$7.27	03/20/2026		M(1)			10,783	(5)	02/07/2029	Common Stock	10,783	$0	214,217	D
Stock Option (right to buy)	$7.27	03/23/2026		M(1)			14,722	(5)	02/07/2029	Common Stock	14,722	$0	199,495	D

Explanation of Responses:

1. The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 18, 2025.

2. The price reported for this transaction is a weighted average price. These shares were sold in multiple transactions at prices ranging from $12.99 to $13.53, inclusive. The reporting person undertakes to provide to Adaptive Biotechnologies Corporation, any security holder of Adaptive Biotechnologies Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in any footnotes to this Form 4.

3. The price reported for this transaction is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.23 to $13.59, inclusive. The reporting person undertakes to provide to Adaptive Biotechnologies Corporation, any security holder of Adaptive Biotechnologies Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in any footnotes to this Form 4.

4. The price reported for this transaction is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.51 to $14.07, inclusive. The reporting person undertakes to provide to Adaptive Biotechnologies Corporation, any security holder of Adaptive Biotechnologies Corporation, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in any footnotes to this Form 4.

5. The option is fully vested and exercisable.

	/s/ Julie Rubinstein by Kyle Piskel, Attorney-in-Fact	03/23/2026
	** Signature of Reporting Person	Date
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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions did Adaptive Biotechnologies (ADPT) President and COO Julie Rubinstein report?

Julie Rubinstein reported exercising options for 44,166 Adaptive Biotechnologies shares at strike prices of $6.55 and $7.27, and selling 57,180 common shares in three open-market transactions at weighted average prices of $13.18, $13.37 and $13.83 per share.

How many Adaptive Biotechnologies (ADPT) shares does Julie Rubinstein hold after the reported Form 4 trades?

After the reported option exercises and share sales, Julie Rubinstein directly holds 481,906 shares of Adaptive Biotechnologies common stock. This figure reflects her position following the March 2026 transactions disclosed in the Form 4 insider trading report.

Were Julie Rubinstein’s Adaptive Biotechnologies (ADPT) stock sales made under a Rule 10b5-1 trading plan?

Yes. The Form 4 footnotes state that all reported transactions were effected pursuant to a Rule 10b5-1 trading plan adopted by Julie Rubinstein on November 18, 2025, indicating the trades were pre-arranged rather than timed at her sole discretion.

What option exercises did Adaptive Biotechnologies (ADPT) report for Julie Rubinstein?

Julie Rubinstein exercised stock options covering 44,166 shares of Adaptive Biotechnologies common stock. The options had exercise prices of $6.55 and $7.27 per share, and one option series is described in the footnotes as fully vested and exercisable.

What is the scale of Julie Rubinstein’s open-market sales of Adaptive Biotechnologies (ADPT) stock?

The Form 4 shows three open-market sales of 19,060 Adaptive Biotechnologies shares each, totaling 57,180 shares. These were sold at weighted average prices of $13.18, $13.37 and $13.83 per share over consecutive trading days.