Certificates
GasID and RecycledID — methodology-specific credentials that verify environmental outcomes and link MassIDs to credits.
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What are certificates?
Certificates are the middle layer of the Carrot Network's credit lifecycle — they sit between MassIDs (which track physical waste) and Credits (which are bought and sold on the market). A certificate represents a single MassID that has passed methodology verification, proving a specific quantity of recycling or emission reductions. Once issued, it is published in the Carrot Registry with the amount of credit it corresponds to. Credits are issued only when the certificate is recorded on the network's public registry: it becomes a non-transferable, tamper-evident record held by the Vault, and a matching amount of fungible credits is created with it (1 credit = 1 metric ton).
This ensures that every credit in circulation is backed by a verified certificate, which is in turn backed by a verified MassID.
Certificate types
The Carrot Network issues certificate types that are tied to methodologies. Each methodology defines which certificate type it issues and which credit symbol is issued:
| Certificate | Credit generated (example) | Issued by | What it verifies |
|---|---|---|---|
| RecycledID | C-BIOW (TRC) when issued under BOLD Recycling | Recycling methodologies | That a specific quantity of waste material was certified recycled at an accredited facility |
| GasID | C-CARB.CH4 (TCC) when issued under BOLD Carbon (CH₄) | Carbon methodologies | That a specific quantity of greenhouse gas emissions (CO₂e) was reduced through waste diversion or biological treatment |
Other methodologies may issue different credit symbols for their certificates.
RecycledID
A RecycledID certificate is issued when a MassID of a specific waste type reaches an accredited Recycler, passes digital MRV (dMRV) verification, and satisfies all rules defined by an active recycling methodology. The certificate records the weight of certified recycled material and references the underlying MassID that proves provenance. Under the BOLD Recycling methodology, each RecycledID generates a corresponding amount of C-BIOW credits; other recycling methodologies may issue different credit symbols.
GasID
A GasID certificate quantifies the greenhouse gas emission reductions achieved through waste diversion or biological treatment instead of disposal in a landfill or dump. GasIDs are generated directly from MassIDs by a carbon methodology: the emission reductions are calculated by comparing the diversion or treatment scenario against the baseline disposal scenario.
The core calculation is: Emission Reductions = Baseline Emissions − Real Emissions. Under the BOLD Carbon (CH₄) methodology, each GasID generates a corresponding amount of C-CARB.CH4 credits (methane reductions); other carbon methodologies may issue different credit symbols.
How certificates are created
This certificate creation flow starts with accumulated MassIDs and passes them through dMRV verification. Verified material produces RecycledID on the recycling branch and GasID on the emissions branch; each certificate is published in the Carrot Registry, and once it is recorded on the public registry it enters the Vault together with its TRC or TCC credits, issued as separate outputs from the same evidence base.
Verified MassIDs produce certificates, published in the Carrot Registry; when a certificate is recorded on the public registry, its credits are minted into the Vault.
The certificate lifecycle follows a clear sequence:
- MassIDs accumulate — As waste moves through the supply chain, MassIDs are created and validated at each transfer point.
- Methodology verification passes — When MassIDs satisfy all rules defined by a specific methodology — whether a recycling methodology (producing a RecycledID) or a carbon methodology (producing a GasID) — the MassIDs become eligible for certification.
- Certificates are issued — Each certificate is issued with its backing MassID, credit type, amount, and methodology context, and is published in the Carrot Registry with the amount of credit it corresponds to. No credit exists for it yet.
- Certificates are recorded and credits are issued — Carrot records certificates on the public registry as inventory is needed, not all at once, and only after the certificate's MassID is recorded there. In a single transaction, the Inventory Manager records the certificate, links it to its parent MassID via the
CertificateRegistry, and issues fungible credits in the matching amount into the Vault as available inventory for credit purchases. A certificate that has not been recorded has no issued credits and cannot back a purchase.
Certificate tracking
Each certificate tracks its available balance as credits are purchased and retired:
- Total amount — Set at issuance, immutable. The total environmental impact this certificate represents.
- Purchased amount — Incremented when credits backed by this certificate are purchased.
- Retired amount — Incremented when purchased credits are permanently retired.
- Available amount — Total minus purchased. The credits still available for sale.
This tracking ensures that every credit purchase and retirement can be traced back to a specific certificate, and through that certificate to the underlying MassID and physical recycling work.