Insider Transactions Reported by 15 Insiders of TECOGEN INC.

Symbol: TGEN on NYSE
Location: North Billerica, MA

Quick Takeaways

TGEN - TECOGEN INC. has 15 insiders with reported activity on this page.
Net insider value flow over the last year: -$690,003.
Recent transaction rows are available for direct filing-level review.

What Changed

Buy value: $134,049; sell value: $824,052.
Net share flow: -91,977.

Why This Matters

This page gives a plain-language issuer insider context before you inspect transaction-level evidence.
Use the filing links below to verify timestamps, codes, and ownership impacts directly from SEC forms.

Source Evidence

Filed on Form 4

Issuer insider activity is sourced from SEC Forms 3, 4, and 5.

See Original Filing

Insider trading overview

Last 12 months

Net insider flow leans to selling over the last 12 months. Net value: -$690,003.

Buys

$134,049

Shares: 60,723

Insiders: 6

Sells

$824,052

Shares: 152,700

Insiders: 2

Net

-$690,003

Shares: -91,977

Insiders: 4

Window (months)	Buy shares	Sell shares	Buy $	Sell $	Net $
0-3	60,723	0	$134,049	$0	+$134,049
3-6	0	0	$0	$0	$0
6-9	0	0	$0	$0	$0
9-12	0	152,700	$0	$824,052	-$824,052

TECOGEN INC. executives and other stock owners filed with the SEC include:

Name	Relationship	Holdings Value	Past Year Net Change	Change %	Valuation	Report Date
John N. Hatsopoulos	Director	$3,795,419			Mixed	20 Mar 2026
John K. Whiting IV	General Counsel & Secretary	$3,594,842	+$23,800	+0.67%	Mixed	23 Mar 2026
Earl R. Lewis	Director	$3,308,863	+$27,005	+0.82%	Mixed	27 Mar 2026
Ann Marie Brown Pacheco	Trustee, 10%+ Owner	$2,886,674			Mixed	04 May 2022
Abinand Rangesh	Chief Executive Officer, Director, Chief Financial Officer	$2,710,536	+$6,894	+0.25%	Mixed	20 Mar 2026
Susan B. Hirsch	Director	$2,242,501	+$44,050	+2%	Mixed	13 Apr 2026
Ahmed Ghoniem	Director	$1,994,987	+$10,000	+0.5%	Mixed	24 Apr 2026
Angelina Galiteva	Director	$1,878,750			Mixed	24 Jul 2025
John M. Albertine	Director	$1,461,250			Mixed	24 Jul 2025
Roger P. Deschenes	Cao	$1,387,831	+$22,300	+1.6%	Mixed	20 Mar 2026
Stephen Lafaille	VP of Business Development	$712,542	-$273,300	-28%	Mixed	24 Jul 2025
Robert A. Panora	COO and President	$521,207	-$550,752	-51%	Mixed	16 Jun 2025
Fred Holubow	Director	$154,000			Mixed	13 Jun 2023
Ralph Jenkins	Director	$132,000			Mixed	23 Jun 2022
Benjamin M. Locke	CEO, Director	$4,616			Mixed	16 Mar 2022

Top shareholders of TECOGEN INC. (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.

Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

Holder	Source	Role / Reporting	Ownership %	Shares	Holdings Value	12M Net Δ	As of	Details
VANGUARD GROUP INC	13F	Company	3.4%	871,840	$4,306,889	—	31 Dec 2025	13F
John N. Hatsopoulos	3/4/5	Director	4.1%	1,038,951 mixed-class rows	$3,795,419	—	20 Mar 2026	3/4/5
Tryfon Natsis	13D/G	Tryfon Natsis and Depoina Pantopoulou, as Joint Tenants with the Right of Survivorship	1.8%	460,300	$3,650,179	$0	30 Jun 2025	13D/G
John K. Whiting IV	3/4/5	General Counsel & Secretary	— mixed-class rows	446,687 mixed-class rows	$3,594,842	+$23,800	23 Mar 2026	3/4/5
BARD ASSOCIATES INC	13F	Company	2.7%	689,107	$3,404,189	—	31 Dec 2025	13F
Earl R. Lewis	3/4/5	Director	— mixed-class rows	1,102,256 mixed-class rows	$3,308,863	+$27,005	27 Mar 2026	3/4/5
Clear Harbor Asset Management, LLC	13F	Company	2.4%	610,000	$3,013,400	—	31 Dec 2025	13F
Ann Marie Brown Pacheco	3/4/5	Trustee, 10%+ Owner	— class O/S missing	3,700,864	$2,886,674	—	04 May 2022	3/4/5
Abinand Rangesh	3/4/5	Chief Executive Officer, Director, Chief Financial Officer	— mixed-class rows	373,316 mixed-class rows	$2,710,536	+$6,894	20 Mar 2026	3/4/5
Susan B. Hirsch	3/4/5	Director	— mixed-class rows	415,416 mixed-class rows	$2,242,501	+$44,050	13 Apr 2026	3/4/5
Portolan Capital Management, LLC	13F	Company	1.7%	445,810	$2,202,301	—	31 Dec 2025	13F
HERALD INVESTMENT MANAGEMENT Ltd	13F	Company	1.6%	420,000	$2,083,200	—	31 Dec 2025	13F
Ahmed Ghoniem	3/4/5	Director	0.05%	12,723 mixed-class rows	$1,994,987	+$10,000	24 Apr 2026	3/4/5
Palisades Investment Partners, LLC	13F	Company	1.5%	390,212	$1,927,647	—	31 Dec 2025	13F
Angelina Galiteva	3/4/5	Director	— class O/S missing	225,000	$1,878,750	—	24 Jul 2025	3/4/5
Arosa Capital Management LP	13F	Company	1.4%	350,000	$1,729,000	—	31 Dec 2025	13F
SUSQUEHANNA INTERNATIONAL GROUP, LLP	13F	Company	1.2%	302,911	$1,496,380	—	31 Dec 2025	13F
John M. Albertine	3/4/5	Director	— class O/S missing	175,000	$1,461,250	—	24 Jul 2025	3/4/5
Jeffrey L. Gendell	13F	Individual	1.2%	295,541	$1,459,973	—	31 Dec 2025	13F
MARSHALL WACE, LLP	13F	Company	1.1%	286,325	$1,414,446	—	31 Dec 2025	13F
Roger P. Deschenes	3/4/5	CAO	— mixed-class rows	205,025 mixed-class rows	$1,387,831	+$22,300	20 Mar 2026	3/4/5
TWO SIGMA INVESTMENTS, LP	13F	Company	0.85%	218,628	$1,080,022	—	31 Dec 2025	13F
JANE STREET GROUP, LLC	13F	Company	0.81%	207,607	$1,025,578	—	31 Dec 2025	13F
BlackRock, Inc.	13F	Company	0.75%	191,360	$945,318	—	31 Dec 2025	13F
GEODE CAPITAL MANAGEMENT, LLC	13F	Company	0.7%	177,914	$879,452	—	31 Dec 2025	13F
Granahan Investment Management, LLC	13F	Company	0.7%	177,822	$878,441	—	31 Dec 2025	13F
Stephen Lafaille	3/4/5	VP of Business Development	— mixed-class rows	102,813 mixed-class rows	$712,542	-$273,300	24 Jul 2025	3/4/5
NEW YORK STATE COMMON RETIREMENT FUND	13F	Company	0.54%	137,200	$677,768	—	31 Dec 2025	13F
HighTower Advisors, LLC	13F	Company	0.52%	132,665	$655,366	—	31 Dec 2025	13F
THOMPSON DAVIS & CO., INC.	13F	Company	0.47%	120,450	$595,023	—	31 Dec 2025	13F
Robert A. Panora	3/4/5	COO and President	— mixed-class rows	192,523 mixed-class rows	$521,207	-$550,752	16 Jun 2025	3/4/5
UBS Group AG	13F	Company	0.41%	104,959	$518,498	—	31 Dec 2025	13F
RAYMOND JAMES FINANCIAL INC	13F	Company	0.39%	99,754	$492,785	—	31 Dec 2025	13F
ROYAL BANK OF CANADA	13F	Company	0.33%	85,519	$423,000	—	31 Dec 2025	13F
Point72 Asset Management, L.P.	13F	Company	0.33%	83,907	$414,501	—	31 Dec 2025	13F
LPL Financial LLC	13F	Company	0.29%	73,793	$364,537	—	31 Dec 2025	13F
MORGAN STANLEY	13F	Company	0.27%	69,978	$345,691	—	31 Dec 2025	13F
STATE STREET CORP	13F	Company	0.27%	69,226	$341,976	—	31 Dec 2025	13F
GOLDMAN SACHS GROUP INC	13F	Company	0.26%	67,724	$334,557	—	31 Dec 2025	13F
PFG Investments, LLC	13F	Company	0.24%	62,523	$308,864	—	31 Dec 2025	13F
MANGROVE PARTNERS IM, LLC	13F	Company	0.24%	61,207	$302,363	—	31 Dec 2025	13F
GROUP ONE TRADING LLC	13F	Company	0.22%	56,578	$279,495	—	31 Dec 2025	13F
CORSAIR CAPITAL MANAGEMENT, L.P.	13F	Company	0.22%	55,017	$271,784	—	31 Dec 2025	13F
XTX Topco Ltd	13F	Company	0.21%	54,763	$270,529	—	31 Dec 2025	13F
RENAISSANCE TECHNOLOGIES LLC	13F	Company	0.21%	54,300	$268,242	—	31 Dec 2025	13F
Diametric Capital, LP	13F	Company	0.21%	53,227	$262,941	—	31 Dec 2025	13F
CITADEL ADVISORS LLC	13F	Company	0.19%	48,920	$241,665	—	31 Dec 2025	13F
SIMPLEX TRADING, LLC	13F	Company	0.18%	46,531	$229,863	—	31 Dec 2025	13F
IMC-Chicago, LLC	13F	Company	0.17%	42,955	$212,198	—	31 Dec 2025	13F
OMERS ADMINISTRATION Corp	13F	Company	0.16%	42,000	$207,480	—	31 Dec 2025	13F

Recent Insider Transactions by Companies or Individuals for TECOGEN INC.

Showing up to 300 most recent insider transactions from the last 12 months.

Insider	Symbol	Class	Transaction	%	Value $	* Price $	Shares	Shares Owned	Date	Ownership
Ahmed Ghoniem	TGEN	Common Stock	Purchase		$10,000	$0.7860	12,723	12,723	24 Apr 2026	Direct
Ahmed Ghoniem	TGEN	Stock Option (Right to Buy)	Options Exercise	-100%			-12,723	0	24 Apr 2026	Direct
Susan F. Hirsch	TGEN	Common Stock	Purchase	1.92%	$18,650	$3.73	5,000	265,416	13 Apr 2026	Direct
Susan F. Hirsch	TGEN	Common Stock	Purchase	3.99%	$25,400	$2.54	10,000	260,416	27 Mar 2026	Direct
Earl R. Lewis	TGEN	Common Stock	Purchase	0.5%	$12,596	$2.52	5,000	1,011,006	27 Mar 2026	Direct
Earl R. Lewis	TGEN	Common Stock	Purchase	0.5%	$14,408	$2.88	5,000	1,006,006	26 Mar 2026	Direct
John K. Whiting IV	TGEN	Common Stock	Purchase	79.3%	$23,800	$2.38	10,000	22,612	23 Mar 2026	Direct
Roger P. Deschenes	TGEN	Common Stock	Purchase	23.3%	$22,300	$2.23	10,000	52,962	20 Mar 2026	Direct
Abinand Rangesh	TGEN	Common Stock	Purchase	4.67%	$6,894	$2.30	3,000	67,193	20 Mar 2026	Direct
John N. Hatsopoulos	TGEN	Common Stock	Options Exercise	5.06%			50,000	1,038,951	20 Mar 2026	Direct
John N. Hatsopoulos	TGEN	Stock Option (Right to Buy)	Options Exercise	-100%			-50,000	0	20 Mar 2026	Direct
John M. Albertine	TGEN	Stock Option (Right to Buy)	Award	16.7%			25,000	175,000	24 Jul 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Award	2994%			11,976	12,376	24 Jul 2025	Direct
Stephen Lafaille	TGEN	Stock Option (Right to Buy)	Award	49.3%			24,075	72,937	24 Jul 2025	Direct
John K. Whiting IV	TGEN	Common Stock	Award	1883%			11,976	12,612	24 Jul 2025	Direct
John K. Whiting IV	TGEN	Stock Option (Right to Buy)	Award	6.02%			24,075	424,075	24 Jul 2025	Direct
Roger P. Deschenes	TGEN	Common Stock	Award	71.9%			17,964	42,962	24 Jul 2025	Direct
Roger P. Deschenes	TGEN	Stock Option (Right to Buy)	Award	8.62%			12,063	152,063	24 Jul 2025	Direct
Abinand Rangesh	TGEN	Common Stock	Award	523.2%			53,892	64,193	24 Jul 2025	Direct
Abinand Rangesh	TGEN	Stock Option (Right to Buy)	Award	13.4%			36,123	306,123	24 Jul 2025	Direct
Susan B. Hirsch	TGEN	Stock Option (Right to Buy)	Award	20%			25,000	150,000	24 Jul 2025	Direct
Ahmed Ghoniem	TGEN	Stock Option (Right to Buy)	Award	11.8%			25,000	237,723	24 Jul 2025	Direct
Earl R. Lewis	TGEN	Stock Option (Right to Buy)	Award	37.7%			25,000	91,250	24 Jul 2025	Direct
Angelina Galiteva	TGEN	Stock Option (Right to Buy)	Award	12.5%			25,000	225,000	24 Jul 2025	Direct
Robert A. Panora	TGEN	Common Stock	Sale	-1.42%	$6,174	$6.86	-900	62,523	24 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Sale	-33.4%	$202,248	$6.36	-31,800	63,423	23 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Sale	-96.2%			-10,000	400	23 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Exercise of in-the-money or at-the-money derivative security	2500%			10,000	10,400	23 Jun 2025	Direct
Stephen Lafaille	TGEN	Stock Options (Right to Buy)	Exercise of in-the-money or at-the-money derivative security	-36.4%			-10,000	17,500	23 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Sale	-12%	$65,390	$5.03	-13,000	95,223	18 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Options Exercise	732.5%			95,223	108,223	16 Jun 2025	Direct
Robert A. Panora	TGEN	Stock Option (Right to Buy)	Options Exercise	-100%			-95,223	0	16 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Exercise of in-the-money or at-the-money derivative security	136%			95,223	165,223	16 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Sale	-98.4%	$149,500	$5.98	-25,000	400	06 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Exercise of in-the-money or at-the-money derivative security	6250%			25,000	25,400	06 Jun 2025	Direct
Stephen Lafaille	TGEN	Stock Options (Right to Buy)	Exercise of in-the-money or at-the-money derivative security	-47.6%			-25,000	27,500	06 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Sale	-70.4%	$155,000	$5.00	-31,000	13,000	04 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Sale	-97.4%	$75,000	$5.00	-15,000	400	04 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Exercise of in-the-money or at-the-money derivative security	3750%			15,000	15,400	04 Jun 2025	Direct
Stephen Lafaille	TGEN	Stock Options (Right to Buy)	Exercise of in-the-money or at-the-money derivative security	-37.5%			-15,000	25,000	04 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Sale	-37.1%	$121,940	$4.69	-26,000	44,000	03 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Sale	-96.2%	$48,800	$4.88	-10,000	400	03 Jun 2025	Direct
Stephen Lafaille	TGEN	Common Stock	Exercise of in-the-money or at-the-money derivative security	2500%			10,000	10,400	03 Jun 2025	Direct
Stephen Lafaille	TGEN	Stock Options (Right to Buy)	Exercise of in-the-money or at-the-money derivative security	-20%			-10,000	40,000	03 Jun 2025	Direct
Robert A. Panora	TGEN	Common Stock	Options Exercise				70,000	70,000	27 May 2025	Direct
Robert A. Panora	TGEN	Stock Options (Right to Buy)	Options Exercise	-35%			-70,000	130,000	27 May 2025	Direct

* An asterisk sign (*) next to the price indicates that the price is likely invalid.