As of May 23, 2026, Tecogen's top three insider holders 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 |
|---|---|---|---|---|
| Earl Lewis | - | 1,011,006 | 0 | 27 Mar, 2026 |
| John Hatsopoulos | Co Chief Executive Officer | 1,038,951 | 0 | 23 Mar, 2026 |
| Roger P. Deschenes | Cao | 52,962 | 0 | 23 Mar, 2026 |
| Robert A Panora | Coo And President | 165,223 | 0 | 20 Jun, 2025 |
| John Kimball Iv Whiting | General Counsel Secretary | 22,612 | 0 | 23 Mar, 2026 |
| Susan B Hirsch | - | 265,416 | 0 | 14 Apr, 2026 |
| Abinand Rangesh | Chief Executive Officer | 67,193 | 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 | Earl Lewis | Common Stock | A | 5,000 | $2.52 | 1,011,006 | D | P |
| 27 Mar, 2026 | Susan B Hirsch | Common Stock | A | 10,000 | $2.54 | 260,416 | D | P |
| 23 Mar, 2026 | John Kimball Iv Whiting | Common Stock | A | 10,000 | $2.38 | 22,612 | D | P |
| 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 | 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 | Abinand Rangesh | Common Stock | A | 3,000 | $2.30 | 67,193 | 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 | John Kimball Iv Whiting | Common Stock | A | 11,976 | $0.00 | 12,612 | D | A |
| 24 Jul, 2025 | Abinand Rangesh | Common Stock | A | 53,892 | $0.00 | 64,193 | 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 | Earl R Lewis | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 91,250 | D | A |
| 24 Jul, 2025 | John Kimball Iv Whiting | Common Stock | A | 11,976 | $0.00 | 12,612 | D | A |
| 24 Jul, 2025 | Roger P. Deschenes | Common Stock | A | 17,964 | $0.00 | 42,962 | D | A |
| 24 Jul, 2025 | Ahmed Ghoniem | Stock Option (Right to Buy) | A | 25,000 | $8.35 | 237,723 | D | A |