For auditors and ESG teams

The audit trail for IMPT carbon retirements

How auditors verify IMPT's per-booking carbon retirements — what evidence exists, where it lives, how to query it.

The chain of evidence

1. Customer makes a booking on app.impt.io. 2. IMPT sources a UN-verified credit from its inventory (Thallo or UCR-routed). 3. The credit is staged as an ERC-1155 NFT. 4. Booking confirmation issued with retirement reference. 5. Credit is retired on-chain — the ERC-1155 is burned, the IMPT ERC-20 token is burned, and the retirement is logged against the booking ID. 6. Real-world registry retirement triggered via Thallo, returning a registry-side proof-of-retirement.

Contracts (verified live)

• IMPT ERC-20 token: 0x04C17b9D3b29A78F7Bd062a57CF44FC633e71f85
• Carbon Credit NFT v2: 0xF473eA545dF03a57beF96BAf96188a6b6d673050
• Sales Manager v2: 0x3a773fFAAF44baa79Bb09dAedC67f261F5964612

Reporting categorisation

Under GHG Protocol Scope 3 Category 6 (business travel), the per-booking offsets should be reported as voluntary credits. They should be presented separately from gross emissions data, in line with SBTi and CSRD guidance. We do not encourage netting offsets against business-travel emissions in headline figures.