IPGP's three largest insider shareholders as of September 29, 2026 are Gapontsev Trust I Valentin (TenPercentOwner, 6.64Mn shares), Fibre Devices Ltd Ip (TenPercentOwner, 6.41Mn shares), Igor Samartsev (Svp, Chief Scientist, 115.70K shares).
| # | Insider | Position | Direct | Indirect | Total | Share of Insiders | Last Filed |
|---|---|---|---|---|---|---|---|
| 1 | Gapontsev Trust I Valentin | TenPercentOwner | 6,642,886 | 0 | 6,642,886 | 48.2% | 03 Sep, 2026 |
| 2 | Fibre Devices Ltd Ip | TenPercentOwner | 6,405,989 | 0 | 6,405,989 | 46.4% | 05 Aug, 2026 |
| 3 | Igor Samartsev | Svp, Chief Scientist | 0 | 115,701 | 115,701 | 0.8% | 13 May, 2026 |
| 4 | Mark Milton Gitin | Ceo | 87,232 | 0 | 87,232 | 0.6% | 08 Jun, 2026 |
| 5 | Timothy Pv Mammen | Svp, Chief Financial Officer | 76,438 | 0 | 76,438 | 0.6% | 26 May, 2026 |
| 6 | Alexander Ovtchinnikov | Svp, Chief Technology Officer | 74,360 | 0 | 74,360 | 0.5% | 05 Mar, 2024 |
| 7 | Michael C Child | Director | 68,625 | 0 | 68,625 | 0.5% | 28 Jun, 2024 |
| 8 | Angelo P Lopresti | Svp, Secretary Gen Counsel | 59,841 | 0 | 59,841 | 0.4% | 01 Jul, 2026 |
| 9 | Eugene A Scherbakov | Ceo | 48,210 | 0 | 48,210 | 0.3% | 04 Aug, 2026 |
| 10 | Trevor Ness | Svp, Chief Revenue Officer | 38,425 | 0 | 38,425 | 0.3% | 03 Mar, 2026 |
| 11 | Felix I Stukalin | Svp, Chief Operating Officer | 36,316 | 0 | 36,316 | 0.3% | 03 Mar, 2023 |
| 12 | Eric Meurice | Director | 25,239 | 0 | 25,239 | 0.2% | 13 May, 2026 |
| 13 | John R Peeler | Director | 20,886 | 0 | 20,886 | 0.2% | 27 Aug, 2026 |
| 14 | Greg Dougherty | Director | 18,334 | 0 | 18,334 | 0.1% | 13 May, 2026 |
| 15 | Gregory R Beecher | Director | 12,216 | 0 | 12,216 | 0.1% | 13 May, 2026 |
| 16 | Thomas J Burgomaster | Chief Accounting Officer | 11,566 | 0 | 11,566 | 0.1% | 04 Mar, 2025 |
| 17 | Kolleen T Kennedy | Director | 11,513 | 0 | 11,513 | 0.1% | 13 May, 2026 |
| 18 | Jeanmarie F. Desmond | Director | 10,486 | 0 | 10,486 | 0.1% | 15 May, 2026 |
| 19 | Tang Agnes | Director | 9,588 | 0 | 9,588 | 0.1% | 23 Jun, 2026 |
| 20 | Thomas J Seifert | Director | 8,946 | 0 | 8,946 | 0.1% | 25 May, 2022 |
| 21 | Paulus Bucher | Svp, Global Operations | 6,053 | 0 | 6,053 | 0.0% | 10 Aug, 2026 |
| 22 | Mary E. Buttarazzi | Vp, Corp Controller And Cao | 4,749 | 0 | 4,749 | 0.0% | 17 Mar, 2026 |
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 |
|---|---|---|---|---|---|---|---|---|
| 01 Sep, 2026 | Gapontsev Trust I Valentin | TenPercentOwner | Disposed S | 18,091 | $75.14 | $1.36Mn | 6,652,192 | Direct |
| 02 Sep, 2026 | Gapontsev Trust I Valentin | TenPercentOwner | Disposed S | 4,591 | $75.65 | $347.31K | 6,647,601 | Direct |
| 02 Sep, 2026 | Gapontsev Trust I Valentin | TenPercentOwner | Disposed S | 4,715 | $76.25 | $359.52K | 6,642,886 | Direct |
| 26 Aug, 2026 | John R Peeler | Director | Acquired P | 1,552 | $72.84 | $113.05K | 19,728 | Direct |
| 26 Aug, 2026 | John R Peeler | Director | Acquired P | 1,158 | $74.57 | $86.35K | 20,886 | Direct |
| 08 Aug, 2026 | Paulus Bucher | Svp, Global Operations | Disposed F | 663 | $90.23 | $59.82K | 6,053 | Direct |
| 04 Aug, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 12,202 | $95.18 | $1.16Mn | 6,424,100 | Direct |
| 05 Aug, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 11,912 | $95.31 | $1.14Mn | 6,412,188 | Direct |
| 05 Aug, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 1,325 | $96.76 | $128.21K | 6,410,863 | Direct |
| 05 Aug, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 4,324 | $97.81 | $422.93K | 6,406,539 | Direct |
| 05 Aug, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 550 | $98.71 | $54.29K | 6,405,989 | Direct |
| 31 Jul, 2026 | Eugene A Scherbakov | Director, TenPercentOwner | Disposed S | 783 | $85.72 | $67.12K | 48,951 | Direct |
| 31 Jul, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 25,994 | $85.76 | $2.23Mn | 6,437,308 | Direct |
| 31 Jul, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 506 | $86.14 | $43.59K | 6,436,802 | Direct |
| 31 Jul, 2026 | Eugene A Scherbakov | Director, TenPercentOwner | Disposed S | 200 | $86.34 | $17.27K | 48,751 | Direct |
| 31 Jul, 2026 | Eugene A Scherbakov | Director, TenPercentOwner | Disposed S | 300 | $87.45 | $26.24K | 48,451 | Direct |
| 31 Jul, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 200 | $87.45 | $17.49K | 6,436,602 | Direct |
| 31 Jul, 2026 | Eugene A Scherbakov | Director, TenPercentOwner | Disposed S | 241 | $88.68 | $21.37K | 48,210 | Direct |
| 31 Jul, 2026 | Fibre Devices Ltd Ip | TenPercentOwner | Disposed S | 300 | $88.59 | $26.58K | 6,436,302 | Direct |
| 21 Jul, 2026 | Gapontsev Trust I Valentin | TenPercentOwner | Disposed S | 1,000 | $100.08 | $100.08K | 6,725,599 | Direct |