As of April 28, 2026, the three largest insider holders of TGEN are John Hatsopoulos (Co Chief Executive Officer, 1.04Mn shares), Earl Lewis (Director, 1.01Mn shares), Earl R Lewis (Director, 635.00K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| John Hatsopoulos | Co Chief Executive Officer | 1,038,951 | 0 | 23 Mar, 2026 |
| Earl Lewis | - | 1,011,006 | 0 | 27 Mar, 2026 |
| Earl R Lewis | - | 0 | 635,000 | 17 Jul, 2024 |
| Susan B Hirsch | - | 265,416 | 0 | 14 Apr, 2026 |
| Robert A Panora | Coo And President | 165,223 | 0 | 20 Jun, 2025 |
| Abinand Rangesh | Chief Executive Officer | 67,193 | 0 | 23 Mar, 2026 |
| Roger P. Deschenes | Cao | 52,962 | 0 | 23 Mar, 2026 |
| John Kimball Iv Whiting | General Counsel Secretary | 22,612 | 0 | 23 Mar, 2026 |
| John Kimball Iv Whiting | General Counsel Secretary | 22,612 | 0 | 23 Mar, 2026 |
| Stephen Lafaille | Vp Of Business Development | 12,376 | 0 | 28 Jul, 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 |
|---|---|---|---|---|---|---|---|---|
| 13 Apr, 2026 | Susan B Hirsch | Common Stock | A | 5,000 | $3.73 | 265,416 | D | P |
| 26 Mar, 2026 | Earl Lewis | Common Stock | A | 5,000 | $2.88 | 1,006,006 | D | P |
| 27 Mar, 2026 | Susan B Hirsch | Common Stock | A | 10,000 | $2.54 | 260,416 | D | P |
| 27 Mar, 2026 | Earl Lewis | Common Stock | A | 5,000 | $2.52 | 1,011,006 | D | P |
| 20 Mar, 2026 | John Hatsopoulos | Common Stock | A | 50,000 | $0.88 | 1,038,951 | D | M |
| 23 Mar, 2026 | John Kimball Iv Whiting | Common Stock | A | 10,000 | $2.38 | 22,612 | D | P |
| 20 Mar, 2026 | Roger P. Deschenes | Common Stock | A | 10,000 | $2.23 | 52,962 | D | P |
| 20 Mar, 2026 | Abinand Rangesh | Common Stock | A | 3,000 | $2.30 | 67,193 | D | P |
| 23 Mar, 2026 | John Kimball Iv Whiting | Common Stock | A | 10,000 | $2.38 | 22,612 | D | P |
| 20 Mar, 2026 | John Hatsopoulos | Stock Option (Right to Buy) | D | 50,000 | $0.88 | 0 | D | M |
| 24 Jul, 2025 | John Kimball Iv Whiting | Common Stock | A | 11,976 | $0.00 | 12,612 | D | A |
| 24 Jul, 2025 | Angelina Galiteva | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 225,000 | D | A |
| 24 Jul, 2025 | John M Albertine | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 175,000 | D | A |
| 24 Jul, 2025 | Abinand Rangesh | Common Stock | A | 53,892 | $0.00 | 64,193 | D | A |
| 24 Jul, 2025 | John Kimball Iv Whiting | Common Stock | A | 11,976 | $0.00 | 12,612 | D | A |
| 24 Jul, 2025 | Ahmed Ghoniem | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 237,723 | D | A |
| 24 Jul, 2025 | Stephen Lafaille | Common Stock | A | 11,976 | $0.00 | 12,376 | D | A |
| 24 Jul, 2025 | Earl R Lewis | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 91,250 | D | A |
| 24 Jul, 2025 | Susan B Hirsch | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 150,000 | D | A |
| 24 Jul, 2025 | Roger P. Deschenes | Common Stock | A | 17,964 | $0.00 | 42,962 | D | A |