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FinancingClosedMarch 17, 2022

Heirloom Series A — limestone-based DAC tech using accelerated carbon mineralization

Heirloom Carbon Series A $53M co-led by Carbon Direct + Ahren + Breakthrough Energy Ventures. Limestone-based DAC tech using accelerated carbon mineralization. Among largest DAC venture rounds at the time. Microsoft Climate Innovation Fund, TIME Ventures, Lowercarbon, Carbon Removal Partners participated. Precursor to Heirloom's first US commercial DAC plant (2023).

$53M

Deal Value

Carbon Capture & DAC

Technology

CA

Location

Deal Details

Deal Type
Strategic & Growth Capital
Buyer / Financier
Carbon Direct Capital + Ahren Innovation Capital + Breakthrough Energy Ventures (co-leads); Microsoft Climate Innovation Fund, Breyer, Grantham, Lowercarbon, TIME Ventures, Carbon Removal Partners, Seven Seven Six
Deal Value
$53M
Stage
Growth
ISO/RTO
CAISO

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