
Founded in 1986, Stonebridge Partners is an operations-oriented private investment firm that invests in middle-market manufacturing, service and distribution businesses, typically seeking control or joint-control positions.
They made 2 investments in the last 12 months. Average disclosed round size is $15.2M (across 16 rounds with reported amounts).
Portfolio
26
Fund Size
$930M
Top Stage
Series B
Last 12 Mo
1
Team
Stephen A. Hanna
Managing Partner, Investment Committee
William G. Connors
Managing Partner, Investment Committee
Andrew A. Thomas
Partner, Investment Committee
Bimal Patel
Operating Partner
Daniel Fulham
Operating Partner
Daniel P. Murphy
Operating Partner
David R. Schopp
Senior Operating Partner
Malcolm Kinnaird
Operating Partner
Ted Anderson
Operating Partner
Timothy K. Coates
Operating Partner
Charles A. Howe
Controller, Chief Compliance Officer
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
Portfolio
| Company | Round | Amount | Date |
|---|---|---|---|
| QQMIT | Unknown | — | Jun 2026 |
| Series B | — | Aug 2025 | |
| Series A | $2.7M | Jan 2025 | |
| Series C | $19.9M | Jun 2024 | |
| Series B | $19.9M | Dec 2022 | |
| Series A | $35M | Dec 2022 | |
| Series B | $16M | Sep 2022 | |
| Series C | $25M | Mar 2022 | |
| Series D | — | Jan 2022 | |
| Unknown | — | Jan 2022 | |
| SS-alpha Therapeutics | Seed | $8.7M | Jul 2021 |
| AAffyXell Therapeutics | Series A | $7.3M | Feb 2021 |
| Series B | $7M | Jan 2020 | |
| Series C | — | Aug 2019 | |
| CCoHive | Series B | $13.5M | Jun 2019 |
| Series B | — | Jan 2019 | |
| SSkelter Labs | Series A | — | Feb 2018 |
| Series C | $11M | Nov 2017 | |
| Series B | $20M | — | |
| Series A | — | — | |
| Series C | — | — | |
| Series D | — | — | |
| Unknown | $20M | — | |
| Series B | $11M | — | |
| Series A | $9M | — |
Top Co-Investors
Last updated: 8 September 2026