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Schema A is the entity attestation — Droplinked’s on-chain receipt that a brand slug has been operator-reviewed and is who it says it is. It anchors the first axis of the 4-axis trust fabric: everything downstream (lender underwriting, peer cross-attestations) presumes the brand identity has been verified.
Schema nameBrandAttestation
EAS revocableyes
Expiry semanticsnone by default (revocation is the lifecycle event)
Issued byDroplinked operator wallet
SubjectMerchant brand slug + shop id
MCP toolverify_brand_attestation
Verifier APIGET /v2/attestations/brand/:slug
Lifecycle guideBrand attestation: request → mint → verify

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Network & UIDs

NetworkEAS contractSchema UIDExplorer
Base mainnet0x42000000000000000000000000000000000000210xf16f6f5c8da93edb3f700c7a5cf2f51bbe738eb1c275a7f5bc7657ef6e27e5a3basescan · easscan schema
Base Sepolia0x4200000000000000000000000000000000000021resolve via chain field on /v2/attestations/brand/:slugsepolia.basescan
EAS registry version: v1.4.0 (EIP-712 typed-data attestations; revocation via revoke(bytes32 uid) direct call).

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Field reference

The on-chain payload is ABI-encoded against the schema string: 
string brandName, uint256 verifiedSince, string kybCohort, string offchainProjectionId
FieldSolidity typeSemanticMutability
brandNamestringDisplay name resolved at issuance time. Used by the public verifier surface and any human-readable consumer.immutable per attestation; a rename re-issues
verifiedSinceuint256Unix seconds. First KYB-approval timestamp for this brand (snapshot — NOT the issuance time of THIS attestation).immutable
kybCohortstringSnapshot of the KybCohort enum at issuance (e.g. "GLOBAL_STANDARD", "GCC_ENHANCED"). Cohort drift is captured by re-issuance, not in-place mutation.immutable per attestation
offchainProjectionIdstringMongo ObjectId of the underlying KybRecord. Allows a verifier with operator-side access to trace back to the supporting documentation; for public verifiers it is opaque.immutable
EAS envelope fields (set by the contract, not by the schema):
Envelope fieldTypeSemantic
uidbytes32The attestation UID. Globally unique per chain. Quote this from MCP / API output.
schemabytes32Schema UID (see table above).
attesteraddressDroplinked operator signing wallet. Mainnet issuer wallet is published on the trust-fabric overview.
recipientaddressThe shop’s recipient wallet if configured; otherwise a deterministic shopId-derived address.
timeuint64Block-mined issuance time.
expirationTimeuint640 (no expiry).
revocationTimeuint640 if active; block time of revoke() otherwise.
revocablebooltrue.
databytesABI-encoded payload per the schema string above.

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Read via Droplinked API

curl -s https://apiv3.droplinked.com/v2/attestations/brand/my-shop-slug | jq .

{
  "found": true,
  "chain": "base",
  "attestationUid": "0x9a3c…ee01",
  "schemaUid": "0xf16f…e5a3",
  "issuer": "0xD5F6FB7b6E71DD7F609b8442951444E5a5C76cce",
  "recipient": "0x…",
  "issuedAt": "2026-06-14T18:08:00Z",
  "status": "ACTIVE",
  "attestationData": {
    "brandName": "My Shop",
    "verifiedSince": "2026-03-02T00:00:00Z",
    "kybCohort": "GLOBAL_STANDARD",
    "offchainProjectionId": "65a3…ef01"
  }
}

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Read via viem (TypeScript)

import { createPublicClient, http, parseAbi, decodeAbiParameters } from "viem";
import { base } from "viem/chains";

const EAS = "0x4200000000000000000000000000000000000021" as const;
const SCHEMA_A = "0xf16f6f5c8da93edb3f700c7a5cf2f51bbe738eb1c275a7f5bc7657ef6e27e5a3" as const;

const client = createPublicClient({ chain: base, transport: http() });

const easAbi = parseAbi([
  "function getAttestation(bytes32 uid) view returns (tuple(bytes32 uid, bytes32 schema, uint64 time, uint64 expirationTime, uint64 revocationTime, bytes32 refUID, address recipient, address attester, bool revocable, bytes data))",
]);

const uid = "0x…"; // UID returned by /v2/attestations/brand/:slug

const att = await client.readContract({
  address: EAS,
  abi: easAbi,
  functionName: "getAttestation",
  args: [uid],
});

// att.schema must equal SCHEMA_A; if not, this is a different schema's UID.
if (att.schema !== SCHEMA_A) throw new Error("not a Schema A attestation");

const [brandName, verifiedSince, kybCohort, offchainProjectionId] =
  decodeAbiParameters(
    [
      { name: "brandName", type: "string" },
      { name: "verifiedSince", type: "uint256" },
      { name: "kybCohort", type: "string" },
      { name: "offchainProjectionId", type: "string" },
    ],
    att.data,
  );

const isActive = att.revocationTime === 0n;
console.log({ brandName, verifiedSince, kybCohort, offchainProjectionId, isActive });

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Read via ethers (TypeScript)

import { JsonRpcProvider, Contract, AbiCoder } from "ethers";

const EAS = "0x4200000000000000000000000000000000000021";
const SCHEMA_A = "0xf16f6f5c8da93edb3f700c7a5cf2f51bbe738eb1c275a7f5bc7657ef6e27e5a3";

const provider = new JsonRpcProvider("https://mainnet.base.org");
const eas = new Contract(
  EAS,
  [
    "function getAttestation(bytes32 uid) view returns (tuple(bytes32 uid, bytes32 schema, uint64 time, uint64 expirationTime, uint64 revocationTime, bytes32 refUID, address recipient, address attester, bool revocable, bytes data))",
  ],
  provider,
);

const uid = "0x…";
const att = await eas.getAttestation(uid);
if (att.schema.toLowerCase() !== SCHEMA_A) throw new Error("schema mismatch");

const [brandName, verifiedSince, kybCohort, offchainProjectionId] =
  AbiCoder.defaultAbiCoder().decode(
    ["string", "uint256", "string", "string"],
    att.data,
  );

const isActive = att.revocationTime === 0n;
console.log({ brandName, verifiedSince, kybCohort, offchainProjectionId, isActive });

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Read via Cast (Foundry)

# Replace UID with the value returned by /v2/attestations/brand/:slug.
cast call 0x4200000000000000000000000000000000000021 \
  "getAttestation(bytes32)((bytes32,bytes32,uint64,uint64,uint64,bytes32,address,address,bool,bytes))" \
  0x9a3cffffffffffffffffffffffffffffffffffffffffffffffffffffffffee01 \
  --rpc-url https://mainnet.base.org

# Decode the `data` field (last element) as the schema payload:
cast abi-decode \
  "x(string,uint256,string,string)" \
  0x…  # the `data` hex from the previous call

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Indexer access (EAS GraphQL)

EAS publishes a public GraphQL indexer per chain. Use it to enumerate without RPC round-trips.

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Common queries

All Schema A attestations for a brand slug — enumerate by attester (Droplinked operator) + schema, then resolve data client-side to filter by brandName. There is no on-chain index on brandName; for scale, use the Droplinked verifier API. 
query LatestForAttester {
  attestations(
    where: {
      schemaId: { equals: "0xf16f6f5c8da93edb3f700c7a5cf2f51bbe738eb1c275a7f5bc7657ef6e27e5a3" }
      attester: { equals: "0xD5F6FB7b6E71DD7F609b8442951444E5a5C76cce" }
      revoked: { equals: false }
    }
    orderBy: { time: desc }
    take: 50
  ) {
    id
    time
    recipient
    revocationTime
    data
  }
}
Single attestation by UID: 
query OneByUid {
  attestation(where: { id: "0x9a3c…ee01" }) {
    id
    schemaId
    attester
    recipient
    time
    revocationTime
    data
  }
}

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Trust assumptions

A Schema A attestation is authoritative if and only if:
  1. The on-chain attester is the Droplinked operator wallet: 0xD5F6FB7b6E71DD7F609b8442951444E5a5C76cce (Base mainnet).
  2. The on-chain schema matches the mainnet UID for Schema A (see top of page).
  3. revocationTime == 0 AND expirationTime == 0 (Schema A is issued without expiry by default).
  4. If issued via a future operator-wallet rotation, the wallet was the registered operator at issuance time — check the time field against the operator-rotation log.
KMS-backed signer rotation is queued (tracking: backend issue #1718). Until it ships, the mainnet issuer is the personal operator wallet listed above. After rotation, this page will be updated and the legacy wallet will remain valid for the historical window.