---
schema_version: "secwatch.filing_event.v1"
accession: "0001537435-25-000134"
form_type: "8-K"
ticker: "TGEN"
cik: "0001537435"
company_name: "TECOGEN INC."
filed_at: "2025-09-04T23:59:59+00:00"
generated_at: "2026-05-17T08:17:18.074829+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.5
calibrated_materiality_score: 0.5
confidence: "high"
source: SEC EDGAR
---

# Tecogen prepays $1M in notes to director Hatsopoulos; eliminates all outstanding debt

## Summary
- Prepaid two promissory notes to director John N. Hatsopoulos totaling $1M principal plus $76,955.62 interest.
- October 2023 note ($500k, 5.12%) and July 2024 note ($500k, 5.06%) repaid on Sept 3 and 4, 2025.
- Aggregate payment of $1,076,955.62 eliminated all outstanding debt of the Company.
- Prepayment avoided approximately $46,159 in future interest charges through original maturity (July 31, 2026).
- Audit Committee approved the prepayment under the Company's Related Person Transactions Policy.

## SEC filing metadata
- accession: 0001537435-25-000134
- form_type: 8-K
- ticker: TGEN
- cik: 0001537435
- company_name: TECOGEN INC.
- filed_at: 2025-09-04T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.5
- calibrated_materiality_score: 0.5
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1537435/000153743525000134/0001537435-25-000134-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1537435/000153743525000134/tgen-20250902.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001537435-25-000134
- JSON: https://secwatch.observer/filing/0001537435-25-000134.json
- Plain text: https://secwatch.observer/filing/0001537435-25-000134.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.