Attestations
Reserve attestations
A holder of crypto can say its reserves are safe from quantum computers. It cannot credibly prove it about itself. A reserve attestation is that proof from an independent party: we read the holder’s published address catalogue from public chain data, report how much sits behind a key that has already been revealed, check the holder’s own stated policy (a cap per address, no address reuse), and sign the result with ML-DSA-65 so anyone can verify it without trusting us or the holder.
Public reserves
Reserves whose holder publishes both its addresses and a policy. Each page re-runs at every visit against the holder’s own catalogue.
- El Salvador Strategic Bitcoin Reserve
National Bitcoin Office of El Salvador (ONBTC)
Policy: no address above 500 BTC; every address hash-protected, never spent from. 20 published addresses.
View the live attestation
Who this is for
Sovereign and corporate treasuries. A government or a public company that holds bitcoin and has told the market how it manages quantum risk needs a way to show the policy holds, on a schedule, from someone who does not hold the keys.
Exchanges and proof of reserves. Proof-of-reserves reports show that coins exist. They do not show how many sit behind a key that is already public. The same address sets an exchange publishes for proof of reserves produce a signed quantum-exposed share of reserves as an appendix.
ETF sponsors and custodians.Spot bitcoin and ether ETF prospectuses now disclose that the quantum risk depends on whether the custodian’s public keys have been exposed and on its key-management practices. That is a disclosure a sponsor must be able to substantiate; a custodian cannot substantiate it about itself.
Hold reserves that are not on a public catalogue, or need an attestation on a schedule under NDA? The method is the same; only the address set is private.
Talk to usMeasure a single holding first: on-chain exposure. How every report is signed and verified.