# Heirloom funding: rounds and investors > Heirloom has raised $203M across 3 rounds since 2022. Investors include Breakthrough Energy, Lowercarbon Capital and Ahren Innovation Capital. Source: https://millionrounds.com/company/heirloom (Millionrounds; every figure on the page links to its filing or article) United States · [Venture startup](https://millionrounds.com/companies) # Who invested in *Heirloom* 3 rounds we have observed, with the 20 investors named in them. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it. Cleantech Climate Tech Web3 & Crypto Follow Heirloom and see its new rounds in your feed. [Start following](https://millionrounds.com/login?join=1&why=follow&next=%2Fcompany%2Fheirloom) Funding summary Updated 5 Nov 2026 **$203M** raised across 3 rounds since 2022, from 4 sources **$53M** Series A **$150M** Series B - **Latest round:** Venture Feb 2025 - **Biggest round:** $150M Series B · Dec 2024 - **Investors:** 20 (5 led) See who backed them ## The funding story Each circle is a round, placed by date and sized by amount. The line above is the running total. 2023 2024 2025 **$53M** Series A **$150M** Series B **?** Venture - **First round:** Series A, $53M - **Biggest round:** $150M - **Usual gap between rounds:** 2.8 years ## The rounds - **Feb 2025** Venture **Amount undisclosed** *2 new* *3 returning* [National Science Foundation](https://millionrounds.com/fund/nsf-small-business-innovation-research-small-business-techno) [Breakthrough Energy](https://millionrounds.com/fund/breakthrough-energy) [Lowercarbon Capital](https://millionrounds.com/fund/lowercarbon-capital) [Seven Seven Six](https://millionrounds.com/fund/seven-seven-six) [AENU](https://millionrounds.com/fund/aenu) Source recorded - **Dec 2024** Series B **$150M** *8 new* *4 returning* [Lowercarbon Capital](https://millionrounds.com/fund/lowercarbon-capital) Lead [Future Positive](https://millionrounds.com/fund/future-positive) Lead [Breakthrough Energy](https://millionrounds.com/fund/breakthrough-energy) [Mitsui & Co](https://millionrounds.com/fund/mitsui-and-co) [Atalanta Therapeutics](https://millionrounds.com/fund/atalanta-therapeutics) [Siemens Financial Services](https://millionrounds.com/fund/siemens-financial-services) [Ahren Innovation Capital](https://millionrounds.com/fund/ahren-innovation-capital) [Carbon Direct Capital](https://millionrounds.com/fund/carbon-direct-capital) [MOL Switch LLC](https://millionrounds.com/fund/mol-switch-llc) [Japan Airlines](https://millionrounds.com/fund/japan-airlines) [MCJ Collective](https://millionrounds.com/fund/mcj-collective) [Quantum Innovation Fund](https://millionrounds.com/fund/quantum-innovation-fund) Reported by Crunchbase News and 1 other - **Mar 2022** Series A **$53M** *10 new* [Breakthrough Energy](https://millionrounds.com/fund/breakthrough-energy) Lead [Ahren Innovation Capital](https://millionrounds.com/fund/ahren-innovation-capital) Lead [Carbon Direct Capital](https://millionrounds.com/fund/carbon-direct-capital) Lead [Lowercarbon Capital](https://millionrounds.com/fund/lowercarbon-capital) [Seven Seven Six](https://millionrounds.com/fund/seven-seven-six) [Breyer Capital](https://millionrounds.com/fund/breyer-capital) [Time Ventures](https://millionrounds.com/fund/time-ventures-2) [Carbon Removal Partners](https://millionrounds.com/fund/carbon-removal-partners) [Grantham Environmental Trust](https://millionrounds.com/fund/grantham-environmental-trust) [The Microsoft Climate Innovation Fund](https://millionrounds.com/fund/the-microsoft-climate-innovation-fund) Reported by Ahren Innovation Capital ## Who was in which round The busiest backers across the latest rounds. A filled square is a round they joined; a dark one, a round they led. **Series A** 2022 **Series B** 2024 **Venture** 2025 [Breakthrough Energy](https://millionrounds.com/fund/breakthrough-energy) L [Lowercarbon Capital](https://millionrounds.com/fund/lowercarbon-capital) L [Ahren Innovation Capital](https://millionrounds.com/fund/ahren-innovation-capital) L [Carbon Direct Capital](https://millionrounds.com/fund/carbon-direct-capital) L [Seven Seven Six](https://millionrounds.com/fund/seven-seven-six) [Future Positive](https://millionrounds.com/fund/future-positive) L [National Science Foundation](https://millionrounds.com/fund/nsf-small-business-innovation-research-small-business-techno) [Breyer Capital](https://millionrounds.com/fund/breyer-capital) [Mitsui & Co](https://millionrounds.com/fund/mitsui-and-co) [AENU](https://millionrounds.com/fund/aenu) ## Everyone who backed them [Breakthrough Energy](https://millionrounds.com/fund/breakthrough-energy) VC firm **3** rounds, led 1 [Lowercarbon Capital](https://millionrounds.com/fund/lowercarbon-capital) VC firm **3** rounds, led 1 [Ahren Innovation Capital](https://millionrounds.com/fund/ahren-innovation-capital) VC firm **2** rounds, led 1 [Carbon Direct Capital](https://millionrounds.com/fund/carbon-direct-capital) VC firm **2** rounds, led 1 [Seven Seven Six](https://millionrounds.com/fund/seven-seven-six) VC firm **2** rounds [Future Positive](https://millionrounds.com/fund/future-positive) VC firm **1** round, led 1 [National Science Foundation](https://millionrounds.com/fund/nsf-small-business-innovation-research-small-business-techno) Government **1** round [Breyer Capital](https://millionrounds.com/fund/breyer-capital) Private equity **1** round [Mitsui & Co](https://millionrounds.com/fund/mitsui-and-co) Corporate VC **1** round [AENU](https://millionrounds.com/fund/aenu) VC firm **1** round [Atalanta Therapeutics](https://millionrounds.com/fund/atalanta-therapeutics) Growth equity **1** round [Siemens Financial Services](https://millionrounds.com/fund/siemens-financial-services) VC firm **1** round [MOL Switch LLC](https://millionrounds.com/fund/mol-switch-llc) Corporate VC **1** round [Time Ventures](https://millionrounds.com/fund/time-ventures-2) VC firm **1** round [Carbon Removal Partners](https://millionrounds.com/fund/carbon-removal-partners) VC firm **1** round [Grantham Environmental Trust](https://millionrounds.com/fund/grantham-environmental-trust) VC firm **1** round [Japan Airlines](https://millionrounds.com/fund/japan-airlines) Growth equity **1** round [MCJ Collective](https://millionrounds.com/fund/mcj-collective) VC firm **1** round [Quantum Innovation Fund](https://millionrounds.com/fund/quantum-innovation-fund) Growth equity **1** round [The Microsoft Climate Innovation Fund](https://millionrounds.com/fund/the-microsoft-climate-innovation-fund) VC firm **1** round Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=heirloom). ## Quick answers about Heirloom ### Who invested in Heirloom? Heirloom's investors include Breakthrough Energy, Lowercarbon Capital, Ahren Innovation Capital, Carbon Direct Capital and Seven Seven Six, and 15 more on record. ### How much has Heirloom raised? Heirloom has raised $203M across 3 rounds since 2022. One round did not disclose an amount, so the total is a floor. ### When did Heirloom last raise? Heirloom's most recent round was a Venture in Feb 2025. ### What was Heirloom's biggest round? Heirloom's largest round on record is $150M (Series B), in Dec 2024, led by Lowercarbon Capital. ### Who backed Heirloom first? Heirloom's first round on record, in Mar 2022, was backed by Breakthrough Energy, Ahren Innovation Capital and Carbon Direct Capital and 7 others. ### What stage is Heirloom at? Heirloom's latest named round is a Venture, in Feb 2025. ### Where is Heirloom based? Heirloom is based in the United States. ### Who led Heirloom's rounds? Breakthrough Energy led the Series A in 2022; Lowercarbon Capital led the Series B in 2024. ## Companies like Heirloom In the same sector, and raised in the last eighteen months. [**Omni** $244M · Nov 2026](https://millionrounds.com/company/omni)[**Predicate** $16M · Oct 2026](https://millionrounds.com/company/predicate)[**DMC Biotechnologies** $19M · Oct 2026](https://millionrounds.com/company/dmc-biotechnologies)[**Terradot** $92M · Oct 2026](https://millionrounds.com/company/terradot)[**Emvolon** $22M · Oct 2026](https://millionrounds.com/company/emvolon)[**Amogy** $125M · Oct 2026](https://millionrounds.com/company/amogy) ## Find investors like these Search every investor by what they have actually funded, then narrow to your stage and market. Free. Open the investor searchOr these rounds in the app