Puro.earth: CORCs, Nasdaq Ownership & the CCP-Eligible Durable Removals Standard

The 2019-founded, Helsinki-based standard majority-owned by Nasdaq that became the eighth ICVCM CCP-Eligible programme in December 2025 — and the methodology rulebook that wrote the first biochar CORC.

By Abhishek Das • April 2026 • 13 min read

1. Why Puro Matters — The First Durable Removals Standard
2. Origin, Nasdaq Ownership & Governance
3. ICVCM CCP-Eligible — 11 December 2025
4. The Five CORC Methodology Families
5. Biochar Methodology Edition 2025 Deep-Dive
6. General Rules v4.2 — The CCP Gate
7. Puro vs Isometric — Where They Compete and Where They Don’t
8. Suppliers, Buyers & Market Position
9. Commercial Implications for Developers & Buyers
10. Frequently Asked Questions
11. What Puro Suppliers & Buyers Should Do Now

Why Puro Matters — The First Durable Removals Standard

Before Isometric, before Frontier, before ICVCM’s engineered CDR category even existed, there was Puro.earth. Founded in Helsinki in 2019, Puro was the first standard purpose-built for durable and engineered carbon removal credits — at a time when no voluntary carbon market registry had a methodology that could certify a tonne of biochar carbon without rewriting the rulebook for nature-based projects. For the better part of five years, if you wanted certified biochar credits in any serious volume, Puro was essentially the only game in town.

That first-mover position still matters. Puro has an installed base of CORCs that most durable-removals competitors cannot match, a biochar methodology that has been through multiple editions and is now retail-eligible, and a registry infrastructure backed by Nasdaq — the only major carbon crediting programme whose controlling owner is a listed exchange operator. In December 2025, ICVCM confirmed Puro as its eighth CCP-Eligible Carbon Crediting Programme, which means Puro CORCs issued under General Rules v4.2 or later are now on a pathway to the CCP label once methodology-level assessment completes.

Origin, Nasdaq Ownership & Governance

Puro.earth was founded in 2019 in Helsinki as a subsidiary of Fortum, the Finnish energy company, with an explicit mission to build the certification infrastructure durable carbon removals needed to scale. It launched with a biochar methodology and has expanded the methodology portfolio methodically since. In June 2021, Nasdaq acquired a majority stake in Puro.earth, making it the only major carbon crediting programme controlled by a listed financial exchange operator. The deal brought exchange-grade registry systems, auditability, counterparty infrastructure and a broader institutional distribution channel to what had previously been a relatively niche Finnish standard.

The Nasdaq relationship matters in two ways. First, it shapes Puro’s registry infrastructure and governance tone: Puro’s systems are built to financial-market standards rather than voluntary-carbon-market conventions, which helps on counterparty diligence and large-buyer procurement. Second, it creates a distribution pipeline for durable-removal credits into institutional buyers who already have Nasdaq exchange relationships. This is a different go-to-market than a voluntary-carbon-market-native registry, and it explains some of the buyer mix on Puro (banks, insurers and exchange-listed corporates feature more heavily than they do on legacy VCM registries).

Governance runs through three layers: the in-house Puro team (responsible for General Rules, methodology authoring and registry operations), an independent Advisory Board (responsible for review and endorsement of methodology changes), and public consultation windows whenever major General Rules or methodology updates are proposed. When the Biochar Methodology Edition 2025 added retail eligibility, that change went through Advisory Board review and a public consultation step before being published.

ICVCM CCP-Eligible — 11 December 2025

On 11 December 2025, the ICVCM Governing Board published decision GB_P-PURO.EARTH_2025_8, confirming Puro.earth as a CCP-Eligible Carbon Crediting Programme. Puro was the eighth programme to achieve CCP-Eligible status, joining ACR, Gold Standard, Verra (VCS), CAR, ART and Isometric. The decision came after an extended assessment of Puro’s governance, procedural integrity, transparency, enforcement mechanisms and the technical requirements embedded in its General Rules.

The CCP-Eligible decision comes with a crucial condition: only credits issued under Puro’s General Rules version 4.2 (or later) are eligible for the CCP label. This is because v4.2 contains the strengthened provisions Puro introduced specifically to meet the CCP requirements — for example updates to additionality screening, uncertainty quantification, permanence handling, and enforcement procedures. Credits issued under earlier General Rules versions remain valid Puro CORCs and can still be retired for voluntary claims, but they cannot carry the CCP label.

Programme-level CCP-Eligible status is not the same as credit-level CCP labelling. For a specific CORC to carry the CCP tag, the underlying methodology must also pass ICVCM category-level assessment. With Puro CCP-Eligible from December 2025, the five Puro methodology families (Biochar, Carbonated Materials, GSC, Woody Biomass Burial, Enhanced Rock Weathering) can now enter ICVCM’s category-level review. Buyers watching this assessment cycle should track it closely: the first Puro methodology approvals will unlock the first Puro CCP-labelled CORCs.

The Five CORC Methodology Families

Puro’s methodology portfolio is narrow and deep: five families covering the main engineered durable-removal pathways, with each family governed by a standalone methodology document and a version history that is openly published on puro.earth. Every CORC on the Puro Registry can be traced to a specific methodology version.

Each methodology defines its own system boundary, calculation formulas, environmental safeguards, monitoring requirements and documentation rules. Third-party auditors verify project submissions against the methodology before CORCs are issued. Different methodologies apply different durability tiers: biochar is typically credited on a decadal-to-centurial basis depending on application pathway and feedstock; Geologically Stored Carbon projects target geological timescales; carbonated materials produce carbonates that are effectively permanent.

Biochar Methodology Edition 2025 Deep-Dive

Biochar is by volume the largest Puro methodology, and the Biochar Methodology Edition 2025 — published in June 2025 — is the version that counts for CCP purposes going forward. Edition 2025 delivered three substantive updates. First, a commercial expansion: retail biochar use to individuals became eligible for CORCs under defined conditions and safeguards. This unlocks volume for small-scale and consumer-facing biochar applications that previous editions had excluded, which had been a long-standing ask from producers whose supply stream was partly retail-facing. Second, tightened MRV requirements aligned with ICVCM CCP expectations on monitoring, reporting and verification — including updates to the permanence calculation factors and the addition of explicit uncertainty handling. Third, alignment with General Rules v4.2, so projects using Edition 2025 under v4.2 are on the CCP pathway.

The retail eligibility change is worth spending time on. Previous editions restricted CORC-eligible biochar to industrial or agricultural applications where chain-of-custody from producer to end-use was cleanly verifiable. Retail applications — biochar sold in bags to gardeners, for example — fell outside that clean chain. Edition 2025 added a framework for retail eligibility under defined conditions and safeguards: tracking the retail pathway, constraints on how retail-destined biochar is labelled and marketed, and requirements on the producer’s ability to substantiate continued permanence claims post-sale. The net effect is that biochar producers whose route-to-market partially goes through retail no longer have to split their production stream between CORC-eligible and non-eligible streams.

For buyers, Edition 2025 biochar CORCs issued under General Rules v4.2 are the tranche of Puro biochar credits positioned to carry the CCP label once methodology-level assessment completes. Earlier vintages remain valid but not on the CCP pathway. If a CCP-labelled biochar portfolio is the target, forward contracts should specifically reference Edition 2025.

General Rules v4.2 — The CCP Gate

Puro’s General Rules are the programme-wide rulebook: the document that governs how projects are registered, how CORCs are issued, how reversals are handled, how disputes are escalated, how the buffer pool (where applicable) is managed, and what transparency is required. Every CORC on the Puro Registry is issued under a specific version of the General Rules. The current CCP-relevant version is v4.2.

The ICVCM CCP-Eligible decision on Puro explicitly applies only to the most recent version (v4.2) of the Puro General Rules, which incorporates strengthened provisions introduced in order to meet the CCP requirements. CORCs issued under earlier General Rules versions (v4.1, v4.0, v2.x and below) remain valid Puro credits and can still be retired for voluntary claims, but they sit outside the CCP-Eligible envelope. In practical terms this means that buyers targeting CCP labelling need to confirm:

• General Rules version: Must be v4.2 or later — the programme-level CCP gate.
• Methodology version: Must be the latest CCP-aligned edition (e.g. Biochar Edition 2025, latest GSC methodology).
• Methodology category approval: For the final CCP label, the methodology itself must also pass ICVCM category-level assessment — still pending as of early 2026 for most Puro methodologies.
• Vintage: CORCs issued before the relevant General Rules and methodology updates came into force are not retroactively CCP-eligible.

Puro vs Isometric — Where They Compete and Where They Don’t

Puro and Isometric are the two durable-removals standards that matter most in 2026, and buyers routinely ask how to think about the two side by side. The short answer is that they are competitors on some pathways (biochar, enhanced rock weathering, GSC) and complements on others (Isometric leads on subsurface biomass burial, bio-oil geological storage, DAC; Puro leads on the installed carbonated materials base and retail-eligible biochar).

For most large corporate buyers, the answer is not “either/or” — it is “both”. Puro provides access to the installed biochar and carbonated materials base; Isometric provides access to the engineered BiCRS, DAC and bio-oil pathways. Together they cover the durable-removals sleeve of a CCP-labelled portfolio more completely than either can alone.

Suppliers, Buyers & Market Position

Puro’s supplier base skews European and biochar-heavy, reflecting its Helsinki origins. Carbofex, the Finnish biochar pioneer, is one of the programme’s longest-running suppliers and issues CORCs from pyrolysis of Nordic forestry residues. Novocarbo (Germany) and Carbon Cycle have deep CORC histories. On the carbonated materials side, Paebbl and O.C.O Technology are among the leading suppliers working with steel slag and industrial byproducts. Enhanced Rock Weathering projects and GSC projects round out the supplier mix.

On the buyer side, Microsoft is the single largest Puro CORC retirer by volume, consistent with its broader position as the largest durable-removals buyer in the world. Shopify, Klarna, Swiss Re, Nasdaq itself and a long list of financial-services corporates make up the rest of the top-tier buyer base. The Nasdaq distribution pipeline has meaningfully shifted Puro’s buyer mix towards institutional finance compared to legacy voluntary carbon market registries.

Commercial Implications for Developers & Buyers

For Puro suppliers, the commercial picture in early 2026 hinges on the General Rules 4.2 cutover and methodology-level CCP assessment. Projects already on Puro need to confirm they are operating under General Rules v4.2 or later, under the latest CCP-aligned methodology edition, and that their documentation will support methodology-level ICVCM review. For biochar producers in particular, the Edition 2025 retail eligibility update is a material commercial unlock that previous methodology versions did not offer.

For Puro buyers, there are two critical due-diligence questions in 2026: is the CORC under General Rules v4.2 or later (the CCP gate), and is the underlying methodology on the pathway to category-level CCP approval? CORCs that fail either test remain valid Puro credits but cannot be retired with the CCP label. Buyers building mixed Puro-Isometric durable-removals portfolios should map each tranche against its CCP status explicitly in the contract, because retirement claims made against a CCP-labelled portfolio depend on every line item meeting the CCP bar.

Frequently Asked Questions

What Puro Suppliers & Buyers Should Do Now

(1) Suppliers: confirm your General Rules version. Only v4.2 or later is on the CCP pathway. If your project is still under an earlier version, prepare for the transition — including any MRV documentation updates required.

(2) Suppliers: upgrade to the latest methodology edition. For biochar specifically, move to Edition 2025 to unlock retail eligibility and CCP alignment. For other methodologies, confirm you are running the latest published edition.

(3) Suppliers: prepare your documentation for category-level review. Puro methodologies now enter ICVCM category-level assessment. MRV, permanence evidence, additionality justification and uncertainty handling should be documented to CCP standards.

(4) Buyers: filter forward contracts by General Rules version. Ask for CORCs issued under v4.2 or later if the CCP label matters to your portfolio. CORCs under earlier versions remain valid voluntary credits but are outside the CCP envelope.

(5) Buyers: map your portfolio against the methodology approval queue. Programme-level CCP-Eligible is the first gate, but methodology-level category approval is required for the final label. Track which Puro methodologies are in active ICVCM review and plan forward purchases accordingly.

(6) Both: use Puro and Isometric as complements, not substitutes. For most large corporate buyers, the durable-removals sleeve is built from both programmes. Puro gives you depth in biochar and carbonated materials; Isometric gives you engineered BiCRS, DAC and bio-oil pathways.

(7) Both: watch the General Rules cadence. Puro updates its General Rules on a regular cycle. Major version changes shift the CCP envelope; minor revisions typically only adjust operational details. Subscribe to Puro’s update feed and your Advisory Board summary of each change.