
Heirloom
formerly Heirloom CarbonRestoring balance to our atmosphere by removing 1 billion tons of carbon dioxide
San Francisco, United States · Founded 2021 · $256.0M raised
- Headquarters
- San Francisco, California
- Employees
- 51–200
- Founded
- 2021
- Business Model
- B2B
- Website
- heirloomcarbon.com
- Total Funding
- $256.0M
- Last Round
- $150.0M Series BDec 2024
- Rounds
- 4
Totals include recorded grants and other qualifying funding, not just equity. What counts toward funding.
About
Heirloom is a direct air capture (DAC) company dedicated to permanently removing carbon dioxide from the atmosphere using a low-cost, scalable technology based on carbon mineralization. The company accelerates the natural process by which limestone (calcium carbonate) absorbs CO2, using engineered systems to cycle limestone through heating and re-exposure to air. Heirloom operates America's first commercial DAC facility and has signed major carbon removal contracts with Microsoft, Shopify, and United Airlines, targeting removal of 1 billion tons of CO2 by 2035.
Summary
Heirloom is a Sustainability company based in San Francisco, United States, founded in 2021. It has raised $256.0M in total across 4 rounds, most recently a $150.0M Series B round in Dec 2024. Investors include Lowercarbon Capital, Breakthrough Energy Ventures and Carbon Direct Capital Management.
Tech & App Stack
3 technologies & apps tracked
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Funding History
Dec 2024
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Funding: Seed through Series B. Amounts, valuations, and investors where available.
Investors
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