Heirloom Carbon

Heirloom Carbon Technologies is a San Francisco-based climate tech company founded in 2020 by Shashank Samala, Zack Bloom, and Noah McQueen. The company has developed a breakthrough direct air capture (DAC) technology that leverages limestone — an abundant and inexpensive mineral — to pull CO2 out of the atmosphere in days rather than the years the natural process takes. The captured CO2 is permanently stored underground. Heirloom opened the first commercial DAC facility in North America (California's Central Valley) in 2023 and is building two additional facilities in Louisiana with combined capacity of nearly 320,000 tons of CO2 per year. All facilities run on 100% renewable energy. Customers include Microsoft, Stripe, Shopify, Meta, JPMorgan, McKinsey, and Autodesk. The $53M known funding corresponds to its Series A (2022); total funding has grown to $203M across 8 rounds.