[Form 4] NPK International Inc. Insider Trading Activity

Rhea-AI Filing Summary

NPK International Inc. executive Lori Briggs reported compensation-related share activity and a small planned sale. On June 1, 2026, restricted stock units covering 24,340 shares vested and converted one-for-one into common stock, with 21,755 shares withheld to cover tax obligations. On June 2, 2026, she sold 10,446 shares of common stock in open-market transactions at a weighted average price of $14.5776 per share under a pre-established Rule 10b5-1 trading plan. Following these transactions, Briggs directly held 255,490 shares of NPK International common stock.

Insider Trade Summary 10b5-1

Net Seller: 10,446 shares ($152,278)

Net Sell 6 txns

Insider Briggs Lori

Role VP & President, Ind. Solutions

Sold 10,446 shs ($152K)

Type	Security	Shares	Price	Value
Sale	Common Stock	10,446	$14.5776	$152K
Exercise	Restricted Stock Units	24,340	$0.00	--
Tax Withholding	Common Stock	5,401	$14.31	$77K
Tax Withholding	Common Stock	9,577	$14.31	$137K
Tax Withholding	Common Stock	6,777	$14.31	$97K
Exercise	Common Stock	24,340	$0.00	--

Holdings After Transaction: Common Stock — 255,490 shares (Direct, null); Restricted Stock Units — 0 shares (Direct, null)

Footnotes (1)

1. Represents shares withheld to satisfy tax withholding obligations upon the vesting of restricted stock units. The restricted stock units vest and convert into shares on a one-for-one basis. The reported sale of 10,446 shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 15, 2025. The price reported is the weighted average price. These shares were sold in multiple transactions in the open market at prices ranging from $14.33 to $14.74, inclusive. The reporting person undertakes to provide to NPK International Inc., any security holder of NPK International Inc., 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 range set forth in footnote (2) to this Form 4. Grant of restricted stock units that vest in one-third increments on June 1 of each subsequent year after grant and settle in shares.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Form 4 Insider Transactions: What Each Field Means →

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^*

Briggs Lori

(Last) (First) (Middle)

9320 LAKESIDE BOULEVARD

SUITE 100

(Street)

THE WOODLANDS TEXAS 77381

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
NPK International Inc. [ NPKI ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	VP & President, Ind. Solutions

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
06/01/2026

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	06/01/2026		F		5,401(1)	D	$14.31	257,950	D
Common Stock	06/01/2026		F		9,577(1)	D	$14.31	248,373	D
Common Stock	06/01/2026		F		6,777(1)	D	$14.31	241,596	D
Common Stock	06/01/2026		M		24,340	A	$0.0(2)	265,936	D
Common Stock	06/02/2026		S		10,446(3)	D	$14.5776(4)	255,490	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
Restricted Stock Units	$0.0(2)	06/01/2026		M			24,340	(5)	(5)	Common Stock	24,340	$0.0	0	D

Explanation of Responses:

1. Represents shares withheld to satisfy tax withholding obligations upon the vesting of restricted stock units.

2. The restricted stock units vest and convert into shares on a one-for-one basis.

3. The reported sale of 10,446 shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 15, 2025.

4. The price reported is the weighted average price. These shares were sold in multiple transactions in the open market at prices ranging from $14.33 to $14.74, inclusive. The reporting person undertakes to provide to NPK International Inc., any security holder of NPK International Inc., 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 range set forth in footnote (2) to this Form 4.

5. Grant of restricted stock units that vest in one-third increments on June 1 of each subsequent year after grant and settle in shares.

	By: M. Celeste Fruge For: Lori Briggs	06/03/2026
	** 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)