Was the NPKI CFO’s share sale made under a Rule 10b5-1 plan?

Yes. A footnote explains the 15,000-share sale occurred automatically under a Rule 10b5-1 trading plan adopted on December 3, 2025 . Such plans pre-schedule trades, reducing the significance of the exact transaction timing.

How are indirect NPKI share holdings reported for the CFO?

The Form 4 shows 65,000 NPKI shares held indirectly "by IRA" , indicating ownership through an individual retirement account. A separate footnote also references shares indirectly held by a trust, highlighting different structures through which holdings can be reported.

CFO sells 15,000 NPK International (NPKI) shares under plan

Q: What did NPKI executive Gregg Piontek report in this Form 4?

Gregg Piontek reported an open-market sale of 15,000 shares of NPK International Inc. common stock. The transaction was executed under a pre-established Rule 10b5-1 trading plan , indicating it was scheduled in advance rather than timed discretionarily.

Q: At what price were the NPKI shares sold by the CFO?

The 15,000 NPKI shares were sold at a weighted average price of $15.045 per share. Footnotes state the individual trades occurred in the open market at prices ranging from $15.00 to $15.10 , inclusive, across multiple transactions.

Q: How many NPKI shares does Gregg Piontek hold after this transaction?

After the reported sale, Gregg Piontek directly holds 819,326 NPKI shares . In addition, a separate line shows 65,000 shares held indirectly through an IRA , reflecting total exposure across both direct and indirect accounts reported in this filing.

Q: What does the price range disclosure mean in this NPKI Form 4?

The filing notes the reported price is a weighted average , with shares sold in multiple open-market trades between $15.00 and $15.10 . The insider undertakes to provide details on the number of shares sold at each price upon request.

Filing Impact

(Moderate)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

NPK International Inc. Senior Vice President and CFO Gregg Piontek sold 15,000 shares of Common Stock in an open-market transaction at a weighted average price of $15.045 per share. The sale was executed automatically under a Rule 10b5-1 trading plan adopted on December 3, 2025. Following the sale, he directly holds 819,326 shares and also has 65,000 shares held indirectly through an IRA.

Insider Trade Summary 10b5-1

Net Seller: 15,000 shares ($225,675)

Net Sell 2 txns

Insider Piontek Gregg

Role Senior Vice President and CFO

Sold 15,000 shs ($226K)

Type	Security	Shares	Price	Value
Sale	Common Stock	15,000	$15.045	$226K
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 819,326 shares (Direct); Common Stock — 65,000 shares (Indirect, by IRA)

Footnotes (1)

The reported sale of 15,000 shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 3, 2025. The price reported is the weighted average price. These shares were sold in multiple transactions in the open market at prices ranging from $15.00 to $15.10, 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. These shares are indirectly held by Trust.

Key Figures

Shares sold: 15,000 shares Weighted average sale price: $15.045 per share Price range: $15.00–$15.10 per share +3 more

6 metrics

Shares sold 15,000 shares Open-market sale on April 9, 2026

Weighted average sale price $15.045 per share Common Stock, multiple open-market trades

Price range $15.00–$15.10 per share Range of individual trade prices in sale

Direct holdings after sale 819,326 shares Common Stock directly owned post-transaction

Indirect IRA holdings 65,000 shares Common Stock held indirectly by IRA

Trading plan adoption date December 3, 2025 Rule 10b5-1 plan governing the 15,000-share sale

Key Terms

Rule 10b5-1 trading plan, weighted average price, open market, IRA, +1 more

5 terms

Rule 10b5-1 trading plan financial

"The reported sale of 15,000 shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 3, 2025."

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

weighted average price financial

"The price reported is the weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

open market financial

"These shares were sold in multiple transactions in the open market at prices ranging from $15.00 to $15.10, inclusive."

An open market is a system where buying and selling of goods, services, or financial assets happen freely without restrictions or special controls. For investors, it means they can trade assets easily and quickly, which helps determine fair prices based on supply and demand. This environment encourages transparency and competition, making it easier to buy or sell with confidence.

IRA financial

"nature_of_ownership": "by IRA""

An individual retirement account (IRA) is a savings account designed to help people put aside money for their retirement, often with tax advantages that encourage long-term savings. It matters to investors because it can grow over time, providing financial security later in life, and offers benefits that can reduce current taxes or allow investments to compound more effectively.

indirectly held by Trust financial

"These shares are indirectly held by Trust."

Form 4 Insider Transactions: What Each Field Means →

04/10/2026 - 05:51 PM

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).

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^*

Piontek Gregg

(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)
	Senior Vice President and CFO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/09/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	04/09/2026		S		15,000⁽¹⁾	D	$15.045⁽²⁾	819,326	D
Common Stock								65,000	I	by IRA⁽³⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. The reported sale of 15,000 shares occurred automatically pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 3, 2025.

2. The price reported is the weighted average price. These shares were sold in multiple transactions in the open market at prices ranging from $15.00 to $15.10, 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.

3. These shares are indirectly held by Trust.

	By: M. Celeste Fruge For: Gregg S. Piontek	04/10/2026
	** 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)

Source: View Original Filing on SEC EDGAR

FAQ

What did NPKI executive Gregg Piontek report in this Form 4?

Gregg Piontek reported an open-market sale of 15,000 shares of NPK International Inc. common stock. The transaction was executed under a pre-established Rule 10b5-1 trading plan, indicating it was scheduled in advance rather than timed discretionarily.

At what price were the NPKI shares sold by the CFO?

The 15,000 NPKI shares were sold at a weighted average price of $15.045 per share. Footnotes state the individual trades occurred in the open market at prices ranging from $15.00 to $15.10, inclusive, across multiple transactions.

How many NPKI shares does Gregg Piontek hold after this transaction?

After the reported sale, Gregg Piontek directly holds 819,326 NPKI shares. In addition, a separate line shows 65,000 shares held indirectly through an IRA, reflecting total exposure across both direct and indirect accounts reported in this filing.

What does the price range disclosure mean in this NPKI Form 4?

The filing notes the reported price is a weighted average, with shares sold in multiple open-market trades between $15.00 and $15.10. The insider undertakes to provide details on the number of shares sold at each price upon request.