Piontek Gregg (CIK 1418328) reported 17 SEC Form 4 insider transactions across 1 companies over the past 18 months (most recent 2026-06-03). Recent activity: Sell NPKI (15,889 shares), Sell NPKI (11,241 shares), Buy NPKI (40,379 shares), Sell NPKI (8,959 shares), Buy NPKI (34,566 shares). Source: SEC Form 4.
| Date | Company | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 15,889 | $227,372 |
| 2026-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 11,241 | $160,859 |
| 2026-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 40,379 | $0 |
| 2026-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 8,959 | $128,203 |
| 2026-05-21 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 34,566 | $0 |
| 2026-04-10 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 15,000 | $225,675 |
| 2026-04-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 35,000 | $507,864 |
| 2026-03-26 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 15,000 | $225,450 |
| 2026-03-05 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 73,590 | $1.0M |
| 2026-03-05 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 73,590 | $317,909 |
| 2026-03-05 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 35,000 | $490,700 |
| 2025-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 43,790 | $0 |
| 2025-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 17,231 | $139,399 |
| 2025-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 15,889 | $128,542 |
| 2025-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Sell | 8,959 | $72,478 |
| 2025-06-03 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 40,379 | $0 |
| 2025-05-16 | NPK International Inc. (NPKI) | Senior Vice President and CFO | Buy | 85,706 | $0 |
Source: SEC Form 4 filings · as of 2026-06-03