FormFactor (FORM) CEO reports 7,669-share sale under Rule 10b5-1 plan

Rhea-AI Filing Summary

FormFactor Inc. CEO and director Mike Slessor reported automatic stock sales under a pre-arranged Rule 10b5-1 trading plan. On December 17, 2025, he sold 5,606 shares of common stock at a weighted average price of $56.19 and an additional 2,063 shares at a weighted average price of $56.82.

These transactions, totaling 7,669 shares, were executed pursuant to a Rule 10b5-1 trading plan adopted on August 19, 2025. After these sales, Slessor beneficially owned 525,601 shares of FormFactor common stock directly.

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^*

SLESSOR MIKE

(Last) (First) (Middle)

7005 SOUTHFRONT ROAD

(Street)

LIVERMORE CA 94551

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
FORMFACTOR INC [ FORM ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
12/17/2025

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

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

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

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	12/17/2025		S		5,606(1)	D	$56.19(2)	527,664	D
Common Stock	12/17/2025		S		2,063(1)	D	$56.82(3)	525,601	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 sale of shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted on August 19, 2025.

2. Price represents the weighted average sale price for the transaction reported. Price range of shares sold is $55.725 through $56.715. Reporting person undertakes to provide upon request by the SEC staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

3. Price represents the weighted average sale price for the transaction reported. Price range of shares sold is $56.72 through $56.8575. Reporting person undertakes to provide upon request by the SEC staff or a security holder of the Issuer, full information regarding the number of shares sold at each separate price.

Remarks:

	/s/ Stan Finkelstein, Attorney-in-fact for Mike Slessor	12/17/2025
	** 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.

FAQ

What insider transaction did FormFactor (FORM) report in this Form 4?

The filing reports that CEO and director Mike Slessor sold a total of 7,669 shares of FormFactor common stock on December 17, 2025 in two separate transactions.

At what prices did Mike Slessor sell FormFactor (FORM) shares?

Slessor sold 5,606 shares at a weighted average price of $56.19 and 2,063 shares at a weighted average price of $56.82, with detailed price ranges noted for each transaction.

How many FormFactor (FORM) shares does the CEO own after these sales?

Following the reported transactions, Mike Slessor beneficially owned 525,601 shares of FormFactor common stock directly.

Were the FormFactor (FORM) insider sales part of a trading plan?

Yes. The sales occurred automatically under a Rule 10b5-1 trading plan that was adopted on August 19, 2025, as disclosed in the explanation of responses.

What is the role of the reporting person in FormFactor (FORM)?

The reporting person, Mike Slessor, is identified as both a Director and an Officer of FormFactor, serving as CEO.

What type of SEC filing is this for FormFactor (FORM)?

This is a Form 4 filing, which reports changes in the beneficial ownership of FormFactor equity securities by an insider, in this case the CEO and director.