Stuart Poulton - 12 Sep 2025 Form 4 Insider Report for Karyopharm Therapeutics Inc. (KPTI)

Role: EVP, Chief Development Officer
Signature: /s/ Nancy Smith as Attorney-in-Fact for Stuart Poulton
Issuer symbol: KPTI
Transactions as of: 12 Sep 2025
Net transactions value: -$2,578
Form type: 4
Filing time: 16 Sep 2025, 16:33:50 UTC
Previous filing: 30 Jul 2025
Next filing: 16 Oct 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Poulton Stuart	EVP, Chief Development Officer	C/O KARYOPHARM THERAPEUTICS INC., 85 WELLS AVENUE, NEWTON	/s/ Nancy Smith as Attorney-in-Fact for Stuart Poulton	16 Sep 2025	0001942597

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	KPTI	Common Stock	Award	$0	+888	+3.3%	$0.000000	28,111	12 Sep 2025	Direct	F1
transaction	KPTI	Common Stock	Sale	$2,578	-401	-1.4%	$6.43	27,710	15 Sep 2025	Direct	F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Represents the number of shares of the issuer's common stock underlying performance-based restricted stock units ("PSUs") granted in February 2023 that have been earned based on the level of achievement of the clinical milestone for complete enrollment in the Company's Phase 3 SENTRY trial, as certified by the issuer's Compensation Committee on September 12, 2025. Each earned PSU represents the contingent right to receive one share of the issuer's common stock upon vesting. The earned PSUs vested on September 12, 2025.
F2	This transaction was effected pursuant to a durable automatic sale instruction plan adopted by the reporting person on May 18, 2022, and represents a broker-assisted sale of shares to satisfy the payment of withholding tax liability incurred upon the vesting of PSUs. The sale does not represent a discretionary trade by the reporting person.

Content

Represents the number of shares of the issuer's common stock underlying performance-based restricted stock units ("PSUs") granted in February 2023 that have been earned based on the level of achievement of the clinical milestone for complete enrollment in the Company's Phase 3 SENTRY trial, as certified by the issuer's Compensation Committee on September 12, 2025. Each earned PSU represents the contingent right to receive one share of the issuer's common stock upon vesting. The earned PSUs vested on September 12, 2025.

This transaction was effected pursuant to a durable automatic sale instruction plan adopted by the reporting person on May 18, 2022, and represents a broker-assisted sale of shares to satisfy the payment of withholding tax liability incurred upon the vesting of PSUs. The sale does not represent a discretionary trade by the reporting person.