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Living Carbon – Seed
Funded Seed · Bay Area, CA · Fund: T-Bird · SH portfolio (0.33% ownership)
Dossier generated 2026-07-14 by /deal-dossier  ·  Deal record: recV4yrG5z1OoYodi  ·  Source: Airtable appjxAR3LPe3fkHOp

One-Liner & Thesis

SH's Seed-round position in Living Carbon — a check in the Bay Area public benefit company using gene-edited trees to make reforestation an economically viable carbon-removal and biomass business. Living Carbon is a public benefit company that engineers hybrid poplar and loblolly pine to accelerate photosynthesis and biomass accumulation, with the wedge of turning degraded mine land and abandoned agricultural acres into cash-flowing reforestation projects that sell both carbon credits and woody biomass feedstock.

Validation at Seed was almost entirely team + syndicate: Maddie Hall (ex-OpenAI special projects, CMC '14) and Patrick Mellor as co-founders, Y Combinator backing, and an early syndicate that later expanded to Felicis, Lowercarbon Capital, Homebrew, Floodgate, Toyota Ventures, and Temasek. SH participated via the T-Bird vehicle for an ultimate 0.33% ownership stake, with the company subsequently raising $36M total across Seed II, Series A, and a 2025 Series B led by Toyota Ventures. The Seed thesis has since been validated by a Microsoft agreement for 1.4M tonnes of carbon removal across Appalachian mine lands and a multi-hundred-million-dollar biomass pipeline anchored by DG Fuels and Biolum.

Investment Score & Recommendation

67/ 100
INVEST

Retrospective Seed-era assessment: the biggest driver is an unusually strong Seed-stage syndicate (Y Combinator + Felicis + Lowercarbon + Homebrew + Floodgate) plus a founder with a rare climate-mission-plus-tech-ops profile; the biggest drag is that at Seed the company was pre-launch with an unproven photosynthesis-enhancement thesis and no revenue, which we can only score generously with the benefit of hindsight.

Momentum: Accelerating Red flags: 1 / 9 Confidence: Low
Market & TAM8/10
25% weight
Team & Founder7/10
25% weight
Product & Traction5/10
20% weight
Deal Terms5/10
20% weight
VC Syndicate9/10
10% weight

Deal Box

Funding Round
Seed
Fund
T-Bird
SH Ownership (current)
0.33%
Company Total Raised (to date)
$36M
Company Latest Valuation
$100M (Airtable; Series B post-money quoted at $95M in 2025-08-29 note)
SH Investment Date
2020-08 (approx.)

Seed-round-specific round size, cap, and SH check size are not recorded in Airtable for this deal. Dollar figures above are company-level totals across all rounds as of the 2025 Series B.

Company Snapshot

Sector
Biotech · Climate
Location
Bay Area, California
Year Founded
2019
Headcount
27 (per 2025-08-29 note) · 5 recorded in Airtable
Total Raised
$36M across 4 rounds
Website
livingcarbon.com
Status
Private · Portfolio
Accelerator
Y Combinator (YC Company tag in CRM)

Market Size

$95.8B
Nature-based Carbon Removal by 2034Web
from $12.4B in 2025
22.3%
CAGR (nature-based CDR)Web
$24.0B
Voluntary Carbon Credit Market by 2030Web
from $4.0B in 2024, 35.1% CAGR
Early
Timing (Seed 2020)

At the time of Seed (Aug 2020), the voluntary carbon credit market was pre-Microsoft-scale demand; Living Carbon was underwriting the bet that corporate net-zero commitments would create durable buyer-side pull for high-quality nature-based removal at 10x current prices. That thesis has since played out: average voluntary carbon prices rose from $8/tCO2e in 2022 to $42/tCO2e in 2025 Web, and the largest hyperscalers (Microsoft, Google, Meta) are now direct offtakers.

Competition

PlayerPositioningFunding / StageEdge vs. them
Living CarbonCRISPR gene-edited hybrid poplar & loblolly pine for accelerated photosynthesis; dual revenue from carbon credits + woody biomassSeed 2020, $36M total, Series B 2025
Chestnut CarbonLarge-scale afforestation on degraded ag land in the Southeastern U.S. using native species; no genetic enhancementFounded 2022 by Kimmeridge; 17M+ trees planted, Microsoft 25-year offtakeLiving Carbon claims higher biomass per acre via biotech traits; Chestnut wins on native-species narrative and speed to scale Web
TerraformationNative-biodiverse reforestation platform (seed banks, solar-desalination, planning software) for community-led projects globallySeries A+; broader software/services modelLiving Carbon competes on unit economics of engineered feedstock vs. Terraformation's platform play Web
Mati CarbonEnhanced rock weathering on smallholder farms in India; mineral-based CO2 sequestration + agronomic co-benefitXPRIZE Carbon Removal grand prize winner (2025)Different modality entirely; competes for the same corporate buyer wallet, not for the same land or approach

Moat: exclusive Oak Ridge National Lab BSTR gene license (peer-reviewed up-to-88% biomass increase in poplar per 2025 Developmental Cell paper, per founder-provided reference in 2025-10-13 note), combined with a land-sourcing playbook targeting degraded mine land where alternative uses are effectively zero — creating both a technical and a land-supply moat.

Traction

Note: no Living Carbon Seed-round DD form is on file in Airtable — the only Forms record for this company was created in 2023 and covers the Series A/B period. Metrics below reflect post-Seed traction that has since validated the original thesis.

1.4M t
Microsoft Carbon OfftakeWeb
announced April 2025
25,000
Acres under Microsoft contractInternal
2,500 planted 2025 YTD
85%
Tree survival on mine landInternal
$2.8M
2025 recognized revenueInternal
$2.7M carbon · $0.1M biomass
$637M
Contracted bookings (20-yr)Internal
2024 basis, per portfolio call
27
Employees (2025)Internal

Exit Potential

Strategic M&A
Likely Path
6–10 yr
Time to Liquidity (from Seed)
Large-cap
Acquirer Profile

Comparable carbon-removal exits are early but signal a maturing acquirer set: Occidental Petroleum acquired Carbon Engineering for $1.1B in 2023 and DAC startup Holocene in 2025, and O&G majors were 3 of the top 5 climate-tech acquirers in 2024 Web. Named plausible acquirers for Living Carbon: energy majors seeking scope-3 offset supply (Oxy, Shell, BP), forest-products companies (Weyerhaeuser, Suzano), or utility/renewable operators — with existing Series B co-investor Octopus Energy already anchoring $500M of project financing exclusivity per 2025-09-29 note. Return math from a Seed entry at low-single-digit millions of implied post-money is highly leveraged to any strategic exit above the current $100M reference valuation.

Founders

Maddie Hall
CEO & Co-founder
Climate tech entrepreneur building Living Carbon, a public benefit company genetically enhancing trees to increase carbon capture and long-term CO2 storage, focused on scalable, nature-based climate solutions. Prior to Living Carbon, Maddie worked on special projects at OpenAI and held various roles in VC and product management (per Airtable Forms record). Claremont McKenna College '14 (Government & Psychology).
Patrick Mellor
Co-founder
Co-founder of Living Carbon. Detailed bio not on file in Airtable; per Company record classified as "Startup Founder" and identified as the technical co-founder counterpart to Maddie.

Open Questions & Risks

Next Steps

Latest Meeting Notes

Note: none of the seven meeting notes linked to Living Carbon are specifically about the Seed decision — the earliest note (2022-08-05) covers the Series A raise and the remainder are 2025 Series B touchpoints. The three most-recent-and-substantive are surfaced here for portfolio context.

2025-10-13 Email update Founder response to Patrick Adams DD questions expand

Written response from Maddie Hall to follow-up diligence questions from Patrick Adams during the Series B raise; covers the biotech-species deployment strategy, mine-land field results, and the peer-reviewed evidence base for growth-rate claims.

Full note

Maddie's responses to Patrick Adams' follow-up questions.

The focus for our biotech-enhanced species is on deployment for biomass projects planted on abandoned agricultural land rather than carbon projects, which utilize mine lands. The traits we develop are not mine land specific.

For Microsoft, Living Carbon has planted 1.28M native trees on degraded mine and agricultural land. To ensure strong performance of all trees on degraded sites, Living Carbon conducts robust site preparation to allow for the soil microbiome to regenerate and roots to take hold. We have seen strong survival across all sites (85%), including the 25,000 enhanced species. Mine lands are highly idiosyncratic and not ideal for field trials, in which we must hold all variables the same and only examine growth rate increase.

We have peer reviewed field trials on our traits. One of our biotech traits has shown up to an 88% biomass increase in third-party field trials conducted by Oak Ridge National Lab. This gives us confidence that we can exceed our 30+% growth rate target in the field to achieve favorable project IRRs.

Two of the biotech enhancements we utilize were developed externally and have a peer-reviewed record of poplar field trials. A 2025 paper in Developmental Cell reports up to an 88% biomass increase and up to a 200% increase in plant height under field conditions in hybrid poplar with the BSTR gene, which we have exclusively licensed from Oak Ridge National Lab for incorporation into other species. A 2023 paper in Nature Communications describes a 38–42% increase in plant height and a 31–35% increase in stem diameter in field trials using a different poplar hybrid.

Source: Meeting Notes reca47aqp5jlUchOX
2025-09-30 Call Series B close mechanics with Octopus & Toyota expand

Call with Maddie covering Octopus Energy's entry as Series B co-lead alongside Toyota Ventures, remaining allocation, and the split between equity and project financing.

Full note

Octopus Energy, the largest renewable-energy provider in the UK, came in and said they wanted to put $12M into the equity then $50M into the project financing in its entirety. Got Octopus's IC approval last week. Have $5–7M remaining. Temasek and LowerCarbon are both participating, as is 776, Tech Energy, and Moroccan Sovereign Wealth Fund. Targeting October 15 as initial close. Will have sufficient capital through 2028–29 to scale the woody biomass business.

Toyota is putting $3.5M in this round; previously did $6.5M (across two financings) — $5M into the A, then another $1.5M in a subsequent financing. Octopus is coming in the second tranche and they are a co-lead with Toyota.

Next steps: Maddie to share updated deck, blurb, and memo; Miles to share LP email for call next Wednesday 9:30–10:30am PST.

Source: Meeting Notes recT3ykFxvMRaDA8p
2025-08-22 Portfolio call LC 2.0: biomass pivot & $637M booked expand

Investor video update walking through Living Carbon's evolution from carbon-credit-only to a dual carbon-plus-biomass business, the specifics of the Microsoft/DG Fuels/Biolum contracts, and the Series B financing structure.

Full note

Secured Series B termsheet from insider Toyota Ventures to lead $30M round on $76M pre-money (flat to Series A). Woody biomass has emerged as significant revenue driver, with two signed contracts totaling $512M with DG and Biolum. Finalizing second Carbon deal alongside Microsoft with Meta, McKinsey, and others.

Business model evolution: shifted from carbon-focused to biomass-focused business after market feedback. Gene-edited trees (using CRISPR) vs traditional GMO approach — customers preferred gene editing. Two main revenue streams: carbon credits and biomass (wood chips). Biomass more profitable than carbon credits.

Microsoft Deal: $127M fixed-price, take-or-pay contract over 20 years. 25,000 acres of degraded mine land (50%) and abandoned agricultural land (50%). Microsoft takes 70% of carbon credits. Additional term sheet with Google, Meta, McKinsey for remaining 30%. Project 100% sold out once second deal closes.

DG Fuels Biomass Contract: 200,000 tons annually for sustainable aviation fuel. Revenue generation starts 2027. 20-year deal, fixed price for first 10 years. $255M total profit opportunity (base case). Requires $65M total project costs. Biolum Deal: milestone-based biomass contract, no upfront financing required from Living Carbon, $60M total profit opportunity, already recognized $100K revenue in 2024.

Superior Biomass Quality: Living Carbon chips $90–120/ton with high energy yield, low carbon intensity (4.3–5.6); waste biomass $40–50/ton but lower energy yield; corn stover $75/ton but high carbon intensity (29 vs Living Carbon's 4.3–5.6). Reliable, uniform feedstock vs variable waste residue. Land Strategy: focus on degraded mine land and abandoned agricultural acres; pay landowners $42/acre annually; sites are liabilities on balance sheets with limited alternative uses; 17,000+ acres in late-stage pipeline.

2024 Performance: $637M in total bookings (over 20-year contracts). Only $2.5M recognized in 2024, ramping significantly over time. On track to plant 2,500 acres for Microsoft by year-end. Biomass pipeline: $1B+ in potential deals, current pipeline represents 1% of US renewable volume obligation, would generate $150M annual biomass value once signed. Unit economics per 1,000 acres planted: carbon revenue $9M+ over contract life, biomass revenue $11M+, Living Carbon costs $220–250K.

Source: Meeting Notes rec6lufxP9Y9eftDr

Deal Timeline

Sources

  1. Crunchbase — Living Carbon Seed Round (2020-08-26) — confirms Seed round date and undisclosed size with six investors.
  2. Crunchbase — Living Carbon company profile — total funding $36M across four rounds; investor list.
  3. PitchBook — Living Carbon company profile — round history and valuation reference.
  4. Y Combinator — Living Carbon — S20 batch listing (referenced in text).
  5. Toyota Ventures — Investment thesis on Living Carbon — post-Seed strategic-investor context and thesis alignment.
  6. PR Newswire via Morningstar (Apr 2025) — Microsoft 1.4M-tonne carbon-removal agreement for Appalachian mine lands.
  7. MarketIntelo — Nature-Based Carbon Removal Market Research Report 2034 — $12.4B → $95.8B TAM figures and 22.3% CAGR; voluntary carbon price trajectory.
  8. Grand View Research — Voluntary Carbon Credit Market Report — $4.0B (2024) → $24.0B (2030), 35.1% CAGR.
  9. Forbes (Apr 2025) — Why Oxy's acquisition of Holocene signals a maturing carbon-removal industry — supports M&A comp set (Oxy/Carbon Engineering $1.1B, Oxy/Holocene).
  10. Chestnut Carbon — company site — competitor positioning (afforestation on degraded ag land, native species, Microsoft offtake).
  11. Terraformation — company site — competitor positioning (native-biodiverse reforestation platform).