Sunstone Partners is a growth-oriented private equity firm founded in 2015 and based in San Mateo, California. The firm invests in AI- and technology-enabled services and software companies through majority and minority transactions, typically targeting businesses with $20M+ in revenue and 20%+ annual growth.
Average disclosed round size is $26.4M (across 28 rounds with reported amounts).
Portfolio
33
Fund Size
$925M
Top Stage
Series A
Last 12 Mo
1
Team
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
DealsAvg Round Size
Portfolio
43 investments
| Company | Round | Amount | Date |
|---|---|---|---|
 Kynexis | Series A | — | Aug 2026 |
| PProgenyHealth | Growth | — | May 2025 |
 Osf Digital | Series C | $100M | Apr 2022 |
| CCloudbakers | Growth | — | Dec 2020 |
 TravelPerk | Series C | $60M | Jul 2019 |
 Peakon | Series B | — | Mar 2019 |
| WWhite Star Capital | Series B | $11M | Feb 2019 |
| GGalecto Biotech | Series C | — | Oct 2018 |
 Taster | Seed | $4M | Jun 2018 |
| TravelPerk | Series B | — | Apr 2018 |
| Peakon | Series B | $22M | Feb 2018 |
 Aula | Seed | $4.2M | Jan 2018 |
| IInboard Technology | Series A | $8M | Nov 2017 |
 Mojiworks | Series A | — | Nov 2017 |
 GetYourGuide | Series D | $75M | Nov 2017 |
| PPrexton Therapeutics | Unknown | — | Feb 2017 |
| PPrexton Therapeutics | Series B | $31M | Jan 2017 |
 Neo4j | Series D | $36M | Nov 2016 |
| FFreespee | Series B | — | Nov 2016 |
 Natural Cycles | Series A | $6M | Jul 2016 |
| TravelPerk | Series A | $7M | Jun 2016 |
| Peakon | Series A | — | Jan 2016 |
 OxThera | Unknown | $32M | Jan 2016 |
 F2G Ltd | Unknown | $60M | Jan 2016 |
 Crate | Seed | $4M | Jan 2016 |
Page 1 of 2
Top Co-Investors
Ysios Capital7 shared
Sunstone Life Science Ventures7 shared
Spark Capital4 shared
Idinvest Partners4 shared
Balderton Capital3 shared
Phoenix Court Group3 shared
Upfront Ventures3 shared
Lifeline Ventures3 shared
Hadean Ventures3 shared
Forbion3 shared
KKR2 shared
Nokia Ventures2 shared
Target Global2 shared
Felix Capital2 shared
EQT Ventures2 shared
Creandum2 shared
Sweet Capital2 shared
coparion2 shared
Fund+2 shared
High-Tech Gründerfonds2 shared
Last updated: 8 September 2026