Key points
- The chain of custody model determines the permissible claim.
- Mass balance does not mean the physical material is certified.
- Claim wording is governed by the scheme's own rules.
The four common models
Identity preserved keeps material from a single certified source separate throughout. Segregated keeps certified material separate but may mix certified sources. Mass balance allows administrative matching of certified volumes. Book-and-claim decouples the certificate from the physical flow entirely.
Matching model to claim
Only identity preserved and segregated support a claim that the physical material is certified. Mass balance and book-and-claim support volume-level claims and must be described accordingly, in the wording the scheme prescribes.
What to verify
- Chain of custody model stated on the transaction documents
- Claim wording matching the scheme's rules for that model
- Certified volumes reconcilable against purchases
Risks to manage
- Physical-product claims made on mass-balance purchases
- Certificate scope not covering the traded product
- Volume claims exceeding certified purchases
Common mistakes
- Treating all certified purchases as equivalent
- Communicating a claim in wording the scheme does not permit
- Not retaining transaction certificates for reconciliation
Frequently asked questions
Is mass balance a weaker option?
It is a different instrument. It supports market development for certified production where physical segregation is impractical, but it does not support a claim about the specific material delivered.
What evidence should be retained?
Transaction certificates, supplier certification details and volume reconciliations for the retention period the scheme requires.
Related reading
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