Attester

An attester is the party that signs an attestation - a cryptographically signed statement that something off-chain is true. The attester is where real-world trust enters a system that otherwise only knows what is on-chain. Their signature is what makes a claim checkable: anyone can verify who said it and that it has not been altered, even if they cannot independently verify the underlying fact.

Attesters show up wherever a token depends on something a blockchain cannot see for itself. For proof of reserves, an auditor or custodian acts as attester, signing that the assets backing a token actually exist and match the supply. For investor eligibility, an accreditation verification provider is the attester, signing that a wallet belongs to someone who qualified as an accredited investor - so a compliant contract can let them in without re-collecting their documents.

The attester is not the same as an oracle, though they are related. An oracle is the delivery mechanism that brings external data on-chain; the attester is the identified, accountable party who vouches that the data is correct. An oracle can carry an attester's signed statement, but the trust rests on the attester, not the pipe.

The critical point for anyone relying on an attestation: it is only as good as the attester. A signature proves who made a claim and that it is intact - not that the claimant was honest or competent. So the real questions are who the attester is, what they actually checked, how recently, and what they are liable for if they are wrong. A reserves attestation from a named auditor carries very different weight from one self-signed by the issuer.

Source: rwa.xyz, as of 2026.