Perma Fix Environmental Services's three largest insider shareholders as of September 09, 2026 are Mark A Zwecker (Director, 247.61K shares), Mark A Zwecker (Director, 244.04K shares), Joe Reeder (Director, 239.34K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Mark A Zwecker | Director | 247,606 | 0 | 247,606 | 18.7% | 02 Jul, 2026 |
| 2 | Joe Reeder | Director | 239,345 | 0 | 239,345 | 18.0% | 02 Jul, 2026 |
| 3 | Louis F Centofanti | Evp Of Strategic Initiatives | 218,765 | 0 | 218,765 | 16.5% | 18 Mar, 2025 |
| 4 | Larry Shelton | Director | 198,983 | 0 | 198,983 | 15.0% | 14 Jul, 2026 |
| 5 | Mark Duff | President And Ceo | 134,556 | 0 | 134,556 | 10.1% | 12 Sep, 2025 |
| 6 | Joseph Timothy Grumski | Director | 67,661 | 0 | 67,661 | 5.1% | 02 Jul, 2026 |
| 7 | Zach Paul Wamp | Director | 53,473 | 0 | 53,473 | 4.0% | 02 Jul, 2026 |
| 8 | Thomas Bostick | Director | 50,610 | 0 | 50,610 | 3.8% | 02 Jul, 2026 |
| 9 | Ben Naccarato | Chief Financial Officer | 48,811 | 0 | 48,811 | 3.7% | 24 Mar, 2025 |
| 10 | Richard Grondin | Evp Of Hanford Int. Waste Op | 41,308 | 0 | 41,308 | 3.1% | 21 Jan, 2026 |
| 11 | Andy Lombardo | Evp Of Nuclear Technical Svc | 17,448 | 0 | 17,448 | 1.3% | 06 Dec, 2023 |
| 12 | Kerry C Duggan | Director | 7,640 | 0 | 7,640 | 0.6% | 02 Jul, 2026 |
| 13 | Troy Eshleman | Chief Operating Officer | 1,350 | 0 | 1,350 | 0.1% | 19 Mar, 2025 |
Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.
| Date | Insider | Position | Transaction | Shares | Price | Value | Shares Held After | Ownership |
|---|---|---|---|---|---|---|---|---|
| 22 Jul, 2026 | Joe Reeder | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 22 Jul, 2026 | Mark A Zwecker | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 22 Jul, 2026 | Kerry C Duggan | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 22 Jul, 2026 | Larry Shelton | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 22 Jul, 2026 | Zach Paul Wamp | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 22 Jul, 2026 | Joseph Timothy Grumski | Director | Acquired A | 10,000 | $0.00 | $0 | 10,000 | Direct |
| 13 Jul, 2026 | Larry Shelton | Director | Acquired M | 2,400 | $4.60 | $11.04K | 198,983 | Direct |
| 13 Jul, 2026 | Larry Shelton | Director | Disposed M | 2,400 | $0.00 | $0 | 0 | Direct |
| 01 Jul, 2026 | Zach Paul Wamp | Director | Acquired A | 849 | $10.72 | $9.10K | 53,473 | Direct |
| 01 Jul, 2026 | Joseph Timothy Grumski | Director | Acquired A | 1,528 | $10.72 | $16.38K | 67,661 | Direct |
| 01 Jul, 2026 | Kerry C Duggan | Director | Acquired A | 819 | $10.72 | $8.78K | 7,640 | Direct |
| 01 Jul, 2026 | Joe Reeder | Director | Acquired A | 1,458 | $10.72 | $15.63K | 239,345 | Direct |
| 01 Jul, 2026 | Larry Shelton | Director | Acquired A | 1,365 | $10.72 | $14.63K | 196,583 | Direct |
| 01 Jul, 2026 | Thomas Bostick | Director | Acquired A | 1,213 | $10.72 | $13.00K | 50,610 | Direct |
| 01 Jul, 2026 | Mark A Zwecker | Director | Acquired A | 1,167 | $10.72 | $12.51K | 247,606 | Direct |
| 01 Apr, 2026 | Joe Reeder | Director | Acquired A | 1,886 | $8.02 | $15.12K | 237,887 | Direct |
| 01 Apr, 2026 | Kerry C Duggan | Director | Acquired A | 1,054 | $8.02 | $8.45K | 6,821 | Direct |
| 01 Apr, 2026 | Larry Shelton | Director | Acquired A | 1,824 | $8.02 | $14.62K | 195,218 | Direct |
| 01 Apr, 2026 | Mark A Zwecker | Director | Acquired A | 1,520 | $8.02 | $12.19K | 244,039 | Direct |
| 01 Apr, 2026 | Zach Paul Wamp | Director | Acquired A | 1,094 | $8.02 | $8.77K | 52,624 | Direct |