Perma Fix Environmental Services's three largest insider shareholders as of April 28, 2026 are Mark A Zwecker (Director, 244.04K shares), Louis F Centofanti (Evp Of Strategic Initiatives, 218.76K shares), Larry Shelton (Director, 195.22K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Mark A Zwecker | - | 244,039 | 0 | 02 Apr, 2026 |
| Louis F Centofanti | Evp Of Strategic Initiatives | 218,765 | 0 | 18 Mar, 2025 |
| Larry Shelton | - | 195,218 | 0 | 02 Apr, 2026 |
| Mark Duff | President And Ceo | 134,556 | 0 | 12 Sep, 2025 |
| Joseph Timothy Grumski | - | 66,133 | 0 | 02 Apr, 2026 |
| Zach Paul Wamp | - | 52,624 | 0 | 02 Apr, 2026 |
| Thomas Bostick | - | 49,397 | 0 | 02 Apr, 2026 |
| Ben Naccarato | Chief Financial Officer | 48,811 | 0 | 24 Mar, 2025 |
| Richard Grondin | Evp Of Hanford Int. Waste Op | 41,308 | 0 | 21 Jan, 2026 |
| Andy Lombardo | Evp Of Nuclear Technical Svc | 17,448 | 0 | 06 Dec, 2023 |
| Kerry C Duggan | - | 6,821 | 0 | 02 Apr, 2026 |
| Troy Eshleman | Chief Operating Officer | 1,350 | 0 | 19 Mar, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 01 Apr, 2026 | Thomas Bostick | Common Stock | A | 1,559 | $8.02 | 49,397 | D | A |
| 01 Apr, 2026 | Larry Shelton | Common Stock | A | 1,824 | $8.02 | 195,218 | D | A |
| 01 Apr, 2026 | Mark A Zwecker | Common Stock | A | 1,520 | $8.02 | 244,039 | D | A |
| 01 Apr, 2026 | Zach Paul Wamp | Common Stock | A | 1,094 | $8.02 | 52,624 | D | A |
| 01 Apr, 2026 | Joseph Timothy Grumski | Common Stock | A | 2,105 | $8.02 | 66,133 | D | A |
| 01 Apr, 2026 | Kerry C Duggan | Common Stock | A | 1,054 | $8.02 | 6,821 | D | A |
| 20 Jan, 2026 | Richard Grondin | Common Stock | A | 5,000 | $7.01 | 39,592 | D | M |
| 20 Jan, 2026 | Richard Grondin | Common Stock | D | 2,555 | $13.71 | 37,037 | D | F |
| 20 Jan, 2026 | Richard Grondin | Common Stock | A | 6,000 | $3.95 | 43,037 | D | M |
| 20 Jan, 2026 | Richard Grondin | Common Stock | D | 1,729 | $13.71 | 41,308 | D | F |
| 20 Jan, 2026 | Richard Grondin | Stock Option | D | 5,000 | $0.00 | 5,000 | D | M |
| 20 Jan, 2026 | Richard Grondin | Stock Option | D | 6,000 | $0.00 | 12,000 | D | M |
| 02 Jan, 2026 | Larry Shelton | Common Stock | A | 1,583 | $9.44 | 193,394 | D | A |
| 02 Jan, 2026 | Zach Paul Wamp | Common Stock | A | 964 | $9.44 | 51,530 | D | A |
| 02 Jan, 2026 | Thomas Bostick | Common Stock | A | 1,324 | $9.44 | 47,838 | D | A |
| 02 Jan, 2026 | Kerry C Duggan | Common Stock | A | 929 | $9.44 | 5,767 | D | A |
| 02 Jan, 2026 | Mark A Zwecker | Common Stock | A | 1,325 | $9.44 | 242,519 | D | A |
| 02 Jan, 2026 | Joseph Timothy Grumski | Common Stock | A | 1,840 | $9.44 | 64,028 | D | A |
| 01 Oct, 2025 | Larry Shelton | Common Stock | A | 1,931 | $7.58 | 191,811 | D | A |
| 01 Oct, 2025 | Zach Paul Wamp | Common Stock | A | 1,201 | $7.58 | 50,566 | D | A |