Tecogen Inc. (TGEN) has 20 known insider and institutional holders on record. The largest holder is BIOGEN IDEC INC with 11,880,448 shares. Other notable holders include ELAN CORP PLC and Pacheco Ann Marie Brown.
Over the last 12 months, insiders have made 38 transactions in TGEN stock — 21 buys (valued at $1.8M) and 9 sells (valued at $896.55K). Insider buying has outpaced selling during this period, which may signal confidence in the company's prospects.
TGEN Insider Ownership
Top Holder
BIOGEN IDEC INC
11,880,448 shares
Buys (12 mo)
21
$1.8M value
Sells (12 mo)
9
$896.55K value
12-Month Transaction Activity
Top Insider Holders
| # |
Name |
Role |
Shares Owned |
Last Filed |
Relative Size |
| 1 |
Biogen Idec Inc |
Director |
11,880,448 |
2005-07-29 |
|
| 2 |
Elan Corp Plc |
10 Percent Owner |
11,626,282 |
2005-01-10 |
|
| 3 |
Pacheco Ann Marie Brown |
10 Percent Owner |
3,700,864 |
2022-05-06 |
|
| 4 |
Hatsopoulos George N |
10 Percent Owner |
1,355,541 |
2016-04-25 |
|
| 5 |
Lewis Earl |
Director |
1,006,006 |
2026-03-27 |
|
| 6 |
Hatsopoulos John |
Director |
988,951 |
2024-09-27 |
|
| 7 |
Benjamin Locke M. |
CEO |
736,800 |
2020-07-21 |
|
| 8 |
Marxe Austin W & Greenhouse David M |
10 Percent Owner |
675,000 |
2009-10-13 |
|
| 9 |
Robinson Bg Susan |
President and CEO |
500,000 |
2009-06-02 |
|
| 10 |
Hirsch Susan B |
Director |
260,416 |
2026-03-27 |
|
| 11 |
Poston David J |
VP, Finance and CFO |
250,000 |
2009-06-02 |
|
| 12 |
Ghoniem Ahmed |
Director |
237,723 |
2025-07-28 |
|
| 13 |
Galiteva Angelina |
Director |
225,000 |
2025-07-28 |
|
| 14 |
Holubow Fred |
Director |
175,000 |
2023-06-15 |
|
| 15 |
Albertine John M |
Director |
175,000 |
2025-07-28 |
|
| 16 |
Jenkins Ralph |
Director |
150,000 |
2022-06-28 |
|
| 17 |
Parker H Stewart |
President & CEO |
131,175 |
2008-05-19 |
|
| 18 |
Petersen Deanna M |
Director |
109,200 |
2020-07-21 |
|
| 19 |
Lewis Earl R |
Director |
91,250 |
2025-07-28 |
|
| 20 |
Cook Jeremy Curnock |
Director |
90,000 |
2009-06-02 |
|
Recent Transactions (last 12 months)
| Date |
Name |
Role |
Type |
Shares |
Price |
Value |
| 2026-03-27 |
Hirsch Susan B |
Director |
Informative Buy |
10,000 |
$2.54 |
$25.4K |
| 2026-03-27 |
Lewis Earl |
Director |
Informative Buy |
5,000 |
$2.52 |
$12.6K |
| 2026-03-26 |
Lewis Earl |
Director |
Informative Buy |
5,000 |
$2.88 |
$14.41K |
| 2026-03-20 |
Rangesh Abinand |
Officer, Other: Chief Executive Officer |
Informative Buy |
3,000 |
$2.30 |
$6.89K |
| 2026-03-23 |
Whiting John Kimball Iv |
General Counsel & Secretary |
Informative Buy |
10,000 |
$2.38 |
$23.8K |
| 2026-03-20 |
Deschenes Roger P. |
CAO |
Informative Buy |
10,000 |
$2.23 |
$22.3K |
| 2026-03-20 |
Hatsopoulos John |
Director |
Option Exercise (Sell) |
50,000 |
$0.88 |
$44K |
| 2025-07-24 |
Lafaille Stephen |
VP of Business Development |
RSU Award |
11,976 |
- |
- |
| 2025-07-24 |
Rangesh Abinand |
Officer, Other: Chief Executive Officer |
RSU Award |
53,892 |
- |
- |
| 2025-07-24 |
Hirsch Susan B |
Director |
RSU Award |
25,000 |
$8.35 |
$208.75K |
| 2025-07-24 |
Whiting John Kimball Iv |
General Counsel & Secretary |
RSU Award |
11,976 |
- |
- |
| 2025-07-24 |
Galiteva Angelina |
Director |
RSU Award |
25,000 |
$8.35 |
$208.75K |
| 2025-07-24 |
Ghoniem Ahmed |
Director |
RSU Award |
25,000 |
$8.35 |
$208.75K |
| 2025-07-24 |
Deschenes Roger P. |
CAO |
RSU Award |
17,964 |
- |
- |
| 2025-07-24 |
Lewis Earl R |
Director |
RSU Award |
25,000 |
$8.35 |
$208.75K |
| 2025-07-24 |
Albertine John M |
Director |
RSU Award |
25,000 |
$8.35 |
$208.75K |
| 2025-06-24 |
Panora Robert A |
COO and President |
Informative Sell |
900 |
$6.86 |
$6.17K |
| 2025-06-23 |
Panora Robert A |
COO and President |
Informative Sell |
31,800 |
$6.36 |
$202.25K |
| 2025-06-18 |
Panora Robert A |
COO and President |
Informative Sell |
13,000 |
$5.03 |
$65.39K |
| 2025-06-16 |
Panora Robert A |
COO and President |
Option Exercise (Sell) |
52,500 |
$1.10 |
$57.75K |
| 2025-06-04 |
Panora Robert A |
COO and President |
Informative Sell |
31,000 |
$5.00 |
$155K |
| 2025-06-03 |
Panora Robert A |
COO and President |
Informative Sell |
26,000 |
$4.69 |
$121.94K |
| 2025-05-27 |
Panora Robert A |
COO and President |
Option Exercise |
70,000 |
$0.71 |
$49.7K |
| 2025-06-23 |
Lafaille Stephen |
VP of Business Development |
Informative Sell |
10,000 |
$7.25 |
$72.5K |
| 2025-06-06 |
Lafaille Stephen |
VP of Business Development |
Informative Sell |
25,000 |
$5.98 |
$149.5K |
