Heirloom

Active#4 worldwide · Carbon capture

Develops direct air capture facilities that use limestone minerals to absorb CO2 from the air, then store it permanently underground or in concrete for carbon removal buyers.

Energy & climate›Carbon capture heirloomcarbon.com

HQUnited States

Last roundSeries B · Dec 2024

Uback rankings

How the AI ranks →

Ranking	Tier	Rank	Edition	Next update
Carbon capture · worldwide	Top 41	#4	Edition 0 (beta) · Oct 2026	20 Oct 2026

Rank historyOct 2026 · #4 Carbon captureFirst edition: no movements yet.

Estimated valuation

AI · Carbon capture ranking (worldwide)

≈ USD 770MUSD 620–970M · Hundreds of M$

Hundreds of k$

Millions $

Tens of M$

Hundreds of M$

Unicorn

Decacorn

Hectocorn

Anchor: Last known equity round: Series B · USD 150M · Dec 2024

An indicative editorial estimate produced by AI, imperfect by nature: neither a financial valuation nor investment advice. Only the market sets a company’s value. Method

Funding history

Date	Round	Amount	Type	Investors
Dec 2024	Series B	USD 150M	Equity	Future Positive, Lowercarbon Capital, Breakthrough Energy Ventures, Mitsubishi, Japan Airlines, Siemens Financial Services

Rounds as cited by Uback’s rankings. Equity, debt and grants are shown separately; only equity rounds count towards the valuation anchor.

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What the AI reads

Read by the AI at the next edition.

Comparable companies in carbon capture

Full carbon capture ranking →

Twelve#3United StatesUnicorn Carbon Clean#5United KingdomHundreds of M$Svante#2CanadaUnicorn Charm Industrial#6United StatesHundreds of M$

Investors in Heirloom: Future Positive · Lowercarbon Capital · Breakthrough Energy Ventures · Mitsubishi · Japan Airlines · Siemens Financial Services

Last updated: Oct 2026Report an error

Uback is a content publisher and an aggregator of non-binding expressions of interest. It provides no investment advice, receives no mandate and takes part in no transaction. Rankings, ranges and brackets are editorial estimates produced by AI, purely indicative.