Does JNJ / USDG match its issuer's published contract?

QED signs a canonical JSON payload. Fetch the public key from /.well-known/qed.json, then check the signature against this payload.

Canonical JSON

{"block":93801670,"chain":"robinhood","checked_at":"2026-10-20T22:37:12Z","dev":false,"expires_at":"2026-10-21T22:37:12Z","issuer":"Robinhood","pool":{"base":{"address":"0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","balance":"81576965375845916136","decimals":18,"symbol":"JNJ"},"chain":"robinhood","dex":"uniswap-v3","pool":"0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","quote":{"address":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","balance":"12112818349","decimals":6,"symbol":"USDG"}},"quote_share_of_supply":0.0931185237310677,"reads":[{"block":93801670,"method":"eth_blockNumber","params":[],"result_hash":"723ecf44a342547b388e1d9d5286798e4eb94c07ff8959165942a6bd7c95a78e","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","token0()"],"raw_result":"0x03dfbbe0ac4e7bcdafd08ed41a400326b77d8c80","result_hash":"e7a2895c61f273d1179adbe58335610eae832c633c0506649f11454c209b23c2","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","token1()"],"raw_result":"0x5fc5360d0400a0fd4f2af552add042d716f1d168","result_hash":"742eb919f060d78d6f55d9d90c592b8d91ea7358553fc7e37cb579cf21192137","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","getReserves()"],"raw_result":"false","result_hash":"076de6e730df0b4c3860877a0f619c6ac11f8aefd78313ac793a2a703c026869","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","slot0()"],"raw_result":"true","result_hash":"18d10c7d2b4b04aaf04254d1ae5d655a5dc0407cbcdd5a8c3986e985370f36ee","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","factory()"],"raw_result":"0x1f7d7550b1b028f7571e69a784071f0205fd2efa","result_hash":"bf7614e6e838b22e4363dfcb3022451641875235ca13e64f8d2d8c3334ff85f3","slot":null},{"block":null,"method":"eth_call","params":["0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","fee()"],"raw_result":"3000","result_hash":"53232d7da9fd2a1931dcd44af08ec415dd52ab8ecc4037ef5e68eb3753978a2e","slot":null},{"block":null,"method":"eth_call","params":["0x1f7d7550B1b028f7571E69A784071F0205FD2EfA","getPool","0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","0xbb8"],"raw_result":"0x7f0ace18d1dced47063cf26e649bc8ab14d09e67","result_hash":"ae3160ef7c2c299662ee7bbcef9a55d01e3b2e7c59d39005166d24e1b5d0dea7","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","symbol()"],"raw_result":"Some(\"JNJ\")","result_hash":"f3de0e5b7b16a6bf3c8711a60c78fb48e6659bec792e9e098853f81cf30029e5","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","balanceOf","0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67"],"raw_result":"Some(\"81576965375845916136\")","result_hash":"9c989030ce4c056b20a1254014c355d0abe06dd124d1510a8e8217245ef71bcf","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","symbol()"],"raw_result":"Some(\"USDG\")","result_hash":"5cbfd9547b12ffd28d96e5f55c97290c4f230a8d7ad7bbe91dc15f2e61c1a3c5","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","decimals()"],"raw_result":"Some(6)","result_hash":"c68fe6989b1835302197d0af5be845dfab10ed9f9632205eb4ab5b949b9e1a6a","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","balanceOf","0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67"],"raw_result":"Some(\"12112818349\")","result_hash":"9de640953dad53b916aea06c9375f6e4788ae2123006b37f74502ccb7d1661ed","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","symbol()"],"raw_result":"Some(\"USDG\")","result_hash":"5cbfd9547b12ffd28d96e5f55c97290c4f230a8d7ad7bbe91dc15f2e61c1a3c5","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","name()"],"raw_result":"Some(\"Global Dollar\")","result_hash":"e34c795a5a7df6a2269bde7247321204357731d7742ef5974b04eb6899db8b11","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","decimals()"],"raw_result":"Some(6)","result_hash":"c68fe6989b1835302197d0af5be845dfab10ed9f9632205eb4ab5b949b9e1a6a","slot":null},{"block":null,"method":"eth_call","params":["0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","totalSupply()"],"raw_result":"Some(\"690137024034160\")","result_hash":"86325987dd2793cc4b7cacd2df9ef05d056ef1b6458c3828ef1db4f43a373446","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","symbol()"],"raw_result":"Some(\"JNJ\")","result_hash":"f3de0e5b7b16a6bf3c8711a60c78fb48e6659bec792e9e098853f81cf30029e5","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","name()"],"raw_result":"Some(\"Johnson & Johnson • Robinhood Token\")","result_hash":"97903a0109760e1e5d45e4b5255bdad6b371c5444b78a25cb608cdee21db7171","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","totalSupply()"],"raw_result":"Some(\"876055183300000000000\")","result_hash":"65d97669410eab4c80204ecdc8e6d5fb9f7d5466b93e74a29ad1903dd10b26cd","slot":null},{"block":null,"method":"eth_call","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","uiMultiplier()"],"raw_result":"1000021490286701962","result_hash":"971345e42cf77d3afc012672ea3eaf15919e8e35d3a83ae8db6207835d6f233d","slot":null},{"block":null,"method":"eth_getCode","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","latest"],"result_hash":"e023f4a2e14683cf62969bf3dc7d7821b1e293e30ebe17f3bc5fd0b223173f25","slot":null},{"block":null,"method":"eth_getCode","params":["0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","latest"],"result_hash":"e023f4a2e14683cf62969bf3dc7d7821b1e293e30ebe17f3bc5fd0b223173f25","slot":null}],"registry_entry":{"chain":"robinhood","contract":"0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","decimals":18,"issuer":"Robinhood","last_checked":"2026-10-20T21:40:19Z","name":"Johnson & Johnson","official_deployments":[{"address":"0x03DfbBE0AC4E7bCDaFd08eD41A400326B77D8c80","network":"Robinhood Chain"}],"source":"robinhood-registry","source_url":"https://api.robinhood.com/rhj/assets","ticker":"JNJ"},"registry_hash":"4de7badd9ace4ee0dba8116c16191391518ae1fb108127285a66d9aa2175fcb1","signer":"GJWKkiUd3zj1pJGfeE7JitiPiwDJC6XmNFvpJWJuvvpn","slot":null,"subject":"0x7F0aCE18D1dCEd47063CF26e649bc8AB14D09e67","ticker":"JNJ","verdict":{"Verified":{"issuer":"Robinhood","ticker":"JNJ"}},"version":1}

Signature

TtzsZJkwx3Liy5SZtrfyIeXnNpEnr0kMgb3TlrTN2dp6xgb9q8tccjQptWzpNSTTojfotU82wgKkEV96+S1CDA==

API call

GET /api/attest/af0be7e4e5e6ec5c922549aa1d2fb0c918b4f222d307819f7072e39cb6bb28fc

1. Fetch the public key and attestation JSON, then verify the signature with the published key.
2. Canonicalize the payload with sorted object keys and no whitespace, then verify its SHA-256 attestation id.
3. Run the API call above and compare the returned payload, serial, signer, and signature with this certificate.