Verastem CFO sells 2,566 shares for tax withholding

The chief financial officer's reported sale satisfied statutory withholding requirements tied to RSU vesting under a Rule 10b5-1 plan.

Rhea-AI Filing Summary

Verastem, Inc. Chief Financial Officer Daniel Calkins reported an award-related acquisition of 8,333 common shares on September 30, 2026. A footnote separately states that 106,893 performance RSUs vested that day after the Compensation Committee determined that performance criteria tied to certain clinical development goals had been achieved. On October 1, Calkins sold 2,566 shares at $8.00 per share to satisfy statutory withholding requirements connected with RSU vesting. The transactions were reported under a Rule 10b5-1 plan.

Insider Trade Summary 10b5-1

Net Seller: 2,566 shares

Net Sell 2 txns

Insider Calkins Daniel

Role Chief Financial Officer

Sold 2,566 shs ($21K)

Type	Security	Shares	Price	Value
Sale	Common Stock F2	2,566	$8.00	$21K
Grant/Award	Common Stock F1	8,333	$0.00	$0.00

Holdings After Transaction: Common Stock — 123,781 shares (Direct)

Footnotes (2)

1. F1. The reported securities were subject to a performance restricted stock units ("RSU") award that was granted on January 21, 2026. 106,893 RSUs vested on September 30, 2026, upon the Issuer's Compensation Committee of the board of directors determining the performance criteria related to certain clinical development goals had been achieved.
2. F2. The sale reported on this Form 4 represents shares sold by the Reporting Person to satisfy statutory withholding requirements in connection with the vesting of RSUs.

Key Figures

Shares sold: 2,566 shares Sale price: $8.00 per share Award-related common shares: 8,333 shares +1 more

4 metrics

Shares sold 2,566 shares October 1, 2026; to satisfy statutory withholding requirements

Sale price $8.00 per share October 1, 2026

Award-related common shares 8,333 shares September 30, 2026

Performance RSUs vested 106,893 RSUs September 30, 2026

Key Terms

performance restricted stock units, statutory withholding requirements, clinical development goals

3 terms

performance restricted stock units financial

"performance restricted stock units ("RSU") award that was granted"

Performance restricted stock units (PRSUs) are promises to deliver company shares to employees or executives only if the business meets specific performance targets and any time-based holding rules. Think of them as a bonus that converts into stock only after set goals are reached, so investors watch PRSUs for two reasons: they can dilute existing shares if paid out, and they signal how closely management’s pay is tied to company performance.

statutory withholding requirements financial

"to satisfy statutory withholding requirements in connection with the vesting of RSUs"

clinical development goals medical

"performance criteria related to certain clinical development goals had been achieved"

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How many VSTM shares did the CFO sell, and at what price?

Daniel Calkins sold 2,566 shares at $8.00 per share on October 1, 2026. The sale satisfied statutory withholding requirements connected with RSU vesting and was reported under a Rule 10b5-1 plan.

How many Verastem RSUs vested, and what triggered vesting?

106,893 RSUs vested on September 30, 2026, after the Compensation Committee determined that performance criteria related to certain clinical development goals had been achieved.

AI-generated analysis. How Rhea-AI works. Not financial advice.

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Available on EDGAR 10/02/2026 - 05:15 PM Accepted by SEC EDGAR 10/02/2026 - 05:15 PM Learn about SEC filing dates

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^*

Calkins Daniel

(Last) (First) (Middle)

C/O VERASTEM, INC.,

117 KENDRICK ST., SUITE 500

(Street)

NEEDHAM MASSACHUSETTS 02494

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Verastem, Inc. [ VSTM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Financial Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
09/30/2026

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	09/30/2026		A		8,333(1)	D	$0.00	126,347	D
Common Stock	10/01/2026		S		2,566(2)	D	$8	123,781	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

Explanation of Responses:

1. The reported securities were subject to a performance restricted stock units ("RSU") award that was granted on January 21, 2026. 106,893 RSUs vested on September 30, 2026, upon the Issuer's Compensation Committee of the board of directors determining the performance criteria related to certain clinical development goals had been achieved.

2. The sale reported on this Form 4 represents shares sold by the Reporting Person to satisfy statutory withholding requirements in connection with the vesting of RSUs.

	/s/ Daniel Calkins	10/02/2026
	** 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)