64 investors have funded 17 Open Source companies head-officed in London, across 95 rounds (Dec 2010 – Feb 2026). They are ranked by how many London companies in this market they have actually backed.
"In London" describes the companies, not the investor: most of the money in any city comes from somewhere else, and the Where the money comes from section below shows exactly where it came from here.
Ranked by companies backed in this market and city, then by round count. "Led" counts rounds recorded with this investor as lead.
| # | Investor | Based in | Stages here | Companies | Rounds | Led | Latest | Portfolio total |
|---|---|---|---|---|---|---|---|---|
| 1 | Y Combinator | Mountain View, United States | Seed | 3 | 3 | 1 | Oct 2025 | 5,648 |
| 2 | Accel | Palo Alto, United States | Series ASeries BSeries C | 2 | 8 | 3 | Oct 2020 | 1,133 |
| 3 | FirstMark | New York City, United States | Series BSeries CSeed | 2 | 5 | 3 | Feb 2026 | 183 |
| 4 | Dawn Capital | London, United Kingdom | Series DSeries A | 2 | 2 | 1 | Sep 2019 | 82 |
| 5 | Ericsson | Stockholm, Sweden | Series BSeries C | 2 | 2 | 1 | Oct 2020 | 40 |
| 6 | Techstars | New York City, United States | Seed | 1 | 2 | — | Jul 2014 | 3,580 |
| 7 | Lightspeed Venture Partners | Menlo Park, United States | Seed | 1 | 2 | 2 | Jun 2024 | 860 |
| 8 | Google Ventures | Mountain View, United States | Series CSeries B | 1 | 2 | 1 | Oct 2020 | 736 |
| 9 | DFJ | Menlo Park, United States | Series BSeries A | 1 | 2 | 2 | May 2016 | 336 |
| 10 | Coatue | New York City, United States | Seed | 1 | 2 | 2 | Jun 2024 | 312 |
| 11 | MMC Ventures | London, United Kingdom | Series CSeries A | 1 | 2 | 1 | Sep 2021 | 135 |
| 12 | Notion | London, United Kingdom | Series BSeries A | 1 | 2 | 1 | Jul 2021 | 139 |
| 13 | General Electric | Boston, United States | Series B | 1 | 2 | 1 | Jul 2019 | 147 |
| 14 | Georgian | Toronto, Canada | Series A | 1 | 2 | 1 | Feb 2026 | 76 |
| 15 | Sound Ventures | United States | Seed | 1 | 2 | 1 | Jun 2024 | 116 |
| 16 | Episode 1 Ventures | London, United Kingdom | Seed | 1 | 2 | 1 | Aug 2021 | 65 |
| 17 | Aspect Ventures | Palo Alto, United States | Series B | 1 | 2 | 1 | Jul 2019 | 61 |
| 18 | CME Group | Chicago, United States | Series DSeries C | 1 | 2 | — | Apr 2019 | 27 |
| 19 | Automattic | San Francisco, United States | Series BSeries A | 1 | 2 | 1 | Jul 2021 | 14 |
| 20 | OSV | New York City, United States | Seed | 1 | 2 | — | Jun 2024 | 7 |
| 21 | ICAP | London, United Kingdom | Series CSeries D | 1 | 2 | 2 | Oct 2016 | 6 |
| 22 | Sequoia Capital | Menlo Park, United States | Seed | 1 | 1 | 1 | Sep 2023 | 1,568 |
| 23 | Global Founders Capital | Berlin, Germany | Seed | 1 | 1 | — | Oct 2025 | 563 |
| 24 | Greycroft | New York City, United States | Seed | 1 | 1 | — | Jun 2024 | 452 |
| 25 | Alumni Ventures | New York City, United States | Series A | 1 | 1 | — | Jun 2024 | 607 |
| 26 | Kima Ventures | Paris, France | Seed | 1 | 1 | — | 636 | |
| 27 | Alchemist Accelerator | San Francisco, United States | Seed | 1 | 1 | 1 | May 2021 | 517 |
| 28 | M12 | San Francisco, United States | Seed | 1 | 1 | 1 | Aug 2021 | 230 |
| 29 | Samsung NEXT | Berlin, Germany | Seed | 1 | 1 | — | Aug 2021 | 242 |
| 30 | Wellington Partners Venture Capital | Munich, Germany | Seed | 1 | 1 | — | 126 | |
| 31 | Firstminute Capital | London, United Kingdom | Series A | 1 | 1 | — | Sep 2019 | 123 |
| 32 | Sunstone | Copenhagen, Denmark | Seed | 1 | 1 | — | Oct 2014 | 89 |
| 33 | OpenView | Boston, United States | Series B | 1 | 1 | 1 | Jul 2019 | 74 |
| 34 | T Capital | Hamburg, Germany | Series C | 1 | 1 | 1 | Oct 2020 | 91 |
| 35 | Scottish Equity Partners | London, United Kingdom | Series C | 1 | 1 | 1 | Sep 2021 | 78 |
| 36 | Cota Capital | San Francisco, United States | Seed | 1 | 1 | — | Aug 2021 | 81 |
| 37 | Tiny | London, United Kingdom | Seed | 1 | 1 | — | Sep 2023 | 100 |
| 38 | Threshold | Menlo Park, United States | Series B | 1 | 1 | — | Jul 2019 | 69 |
| 39 | Protocol Labs | Palo Alto, United States | Series B | 1 | 1 | 1 | Jul 2021 | 89 |
| 40 | Zetta Venture Partners | San Francisco, United States | Seed | 1 | 1 | 1 | Jun 2020 | 53 |
| 41 | DTCP | Hamburg, Germany | Series C | 1 | 1 | — | Oct 2020 | 65 |
| 42 | Metaplanet | Tallinn, Estonia | Series B | 1 | 1 | — | Jul 2021 | 70 |
| 43 | Bright Pixel Capital | Maia, Portugal | Series C | 1 | 1 | 1 | Oct 2020 | 58 |
| 44 | Orange Ventures | Paris, France | Series C | 1 | 1 | 1 | Oct 2020 | 51 |
| 45 | Root Ventures | San Francisco, United States | Seed | 1 | 1 | 1 | Jun 2020 | 38 |
| 46 | Gresham House Ventures | London, United Kingdom | Series A | 1 | 1 | 1 | Jan 2024 | 46 |
| 47 | Allianz X | Munich, Germany | Series E+ | 1 | 1 | 1 | Feb 2022 | 37 |
| 48 | Equistone Partners Europe | London, United Kingdom | Seed | 1 | 1 | — | Apr 2015 | 35 |
| 49 | Redline Capital Management | Luxembourg, Luxembourg | Series C | 1 | 1 | — | Oct 2020 | 23 |
| 50 | Openfund | Athens, Greece | Series A | 1 | 1 | — | Apr 2015 | 24 |
| 51 | Chalfen Ventures | London, United Kingdom | Series A | 1 | 1 | — | Feb 2026 | 25 |
| 52 | Firestartr | London, United Kingdom | Seed | 1 | 1 | — | 27 | |
| 53 | Begin Capital | London, United Kingdom | Series A | 1 | 1 | — | Feb 2026 | 21 |
| 54 | Amazon Web Services | Seattle, United States | Series C | 1 | 1 | 1 | Oct 2020 | 17 |
| 55 | Crew Capital | New York City, United States | Series A | 1 | 1 | — | Jun 2024 | 15 |
| 56 | Remote First Capital | Fort Lauderdale, United States | Seed | 1 | 1 | — | Sep 2023 | 15 |
| 57 | Karlani Capital | New York City, United States | Seed | 1 | 1 | — | Sep 2014 | 11 |
| 58 | LoneTree Capital | New York City, United States | Series C | 1 | 1 | — | Jan 2026 | 6 |
| 59 | Untitled Ventures | Seed | 1 | 1 | — | Sep 2023 | 5 | |
| 60 | Cursor Capital | New York City, United States | Seed | 1 | 1 | — | Sep 2023 | 4 |
| 61 | Bolts Capital | Series A | 1 | 1 | — | Jul 2024 | 4 | |
| 62 | Japan Exchange Group | Tokyo, Japan | Series D | 1 | 1 | 1 | Jan 2017 | 3 |
| 63 | Status | Switzerland | Seed | 1 | 1 | — | Jan 2018 | 2 |
| 64 | Soracom | Tokyo, Japan | Series B | 1 | 1 | 1 | Jun 2018 | 2 |
Head office of the investors on this page.
Rounds by stage — where in a company's life this money arrives.
Total disclosed size of each round, not one investor's share.
How active this market has been.
Open Source companies head-officed in London that took money from these investors.
| Company | Backers | Rounds | Disclosed | Latest round |
|---|---|---|---|---|
| Weaveworks weave.works |
9 | 12 | $364.8M | Series C Oct 2020 |
| Balena balena.io |
9 | 12 | $147M | Series C Jan 2026 |
| OpenGamma opengamma.com |
7 | 14 | $162M | Series E+ Feb 2022 |
| Element element.io |
7 | 9 | $155.1M | Series B Jul 2021 |
| SurrealDB surrealdb.com |
6 | 9 | $178M | Series A Feb 2026 |
| Stability AI stability.ai |
5 | 9 | $728M | Seed Jun 2024 |
| Webiny webiny.com |
5 | 6 | $14.5M | Seed Aug 2021 |
| PartyKit partykit.io |
5 | 5 | $12.5M | Seed Sep 2023 |
| Cloud 66 cloud66.com |
5 | 6 | $3.2M | Seed Sep 2014 |
| HASH hash.ai |
3 | 3 | $15M | Series A Jul 2024 |
| Tyk.io tyk.io |
2 | 3 | $75M | Series C Sep 2021 |
| shuttle shuttle.rs |
2 | 2 | $12M | Seed Oct 2025 |
| Ozone ozoneapi.com |
1 | 1 | $10.8M | Series A Jan 2024 |
| Fliplet fliplet.com |
1 | 1 | $746K | Seed Apr 2015 |
| Heroic Labs heroiclabs.com |
1 | 1 | $120K | Seed Jun 2015 |
| Skylable skylable.com |
1 | 1 | — | Seed Oct 2014 |
| Ant Media antmedia.io |
1 | 1 | — | Seed May 2021 |
| Date | Investor | Company | Stage | Round size |
|---|---|---|---|---|
| Feb 2026 | FirstMark | SurrealDB | Series A | $23M |
| Feb 2026 | Chalfen Ventures | SurrealDB | Series A | $23M |
| Feb 2026 | Begin Capital | SurrealDB | Series A | $23M |
| Feb 2026 | Georgian | SurrealDB | Series A | $23M |
| Jan 2026 | LoneTree Capital | Balena | Series C | — |
| Oct 2025 | Global Founders Capital | shuttle | Seed | $6M |
| Oct 2025 | Y Combinator | shuttle | Seed | $6M |
| Jul 2024 | Bolts Capital | HASH | Series A | $10M |
| Jun 2024 | Lightspeed Venture PartnersLED | Stability AI | Seed | $80M |
| Jun 2024 | Greycroft | Stability AI | Seed | $80M |
| Jun 2024 | CoatueLED | Stability AI | Seed | $80M |
| Jun 2024 | Sound Ventures | Stability AI | Seed | $80M |
| Jun 2024 | OSV | Stability AI | Seed | $80M |
| Jun 2024 | Crew Capital | SurrealDB | Series A | $20M |
| Jun 2024 | Alumni Ventures | SurrealDB | Series A | $20M |
| Jun 2024 | GeorgianLED | SurrealDB | Series A | $20M |
| Jun 2024 | FirstMarkLED | SurrealDB | Series A | $20M |
| Jan 2024 | Gresham House VenturesLED | Ozone | Series A | $10.8M |
| Sep 2023 | Sequoia CapitalLED | PartyKit | Seed | $2.5M |
| Sep 2023 | Tiny | PartyKit | Seed | $2.5M |
Open Source investors in other cities
Other markets in London