Does NVDA / 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":91997761,"chain":"robinhood","checked_at":"2026-10-18T18:54:53Z","dev":false,"expires_at":"2026-10-19T18:54:53Z","issuer":"Robinhood","pool":{"base":{"address":"0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","balance":"504150197752","decimals":6,"symbol":"USDG"},"chain":"robinhood","dex":"uniswap-v3","pool":"0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","quote":{"address":"0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","balance":"11877109264683094459350","decimals":18,"symbol":"NVDA"}},"quote_share_of_supply":0.13175113396481047,"reads":[{"block":91997761,"method":"eth_blockNumber","params":[],"result_hash":"cc3bcf4b2c362f921ba6e8dbde48eac94b6279d8b8d1e4ae7f9c432d71f46cdb","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","token0()"],"raw_result":"0x5fc5360d0400a0fd4f2af552add042d716f1d168","result_hash":"742eb919f060d78d6f55d9d90c592b8d91ea7358553fc7e37cb579cf21192137","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","token1()"],"raw_result":"0xd0601ce157db5bdc3162bbac2a2c8af5320d9eec","result_hash":"837593898070a9209e25b8e838227fd9a1d34f048e67360db2591dc0ee9b7688","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","getReserves()"],"raw_result":"false","result_hash":"076de6e730df0b4c3860877a0f619c6ac11f8aefd78313ac793a2a703c026869","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","slot0()"],"raw_result":"true","result_hash":"18d10c7d2b4b04aaf04254d1ae5d655a5dc0407cbcdd5a8c3986e985370f36ee","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","factory()"],"raw_result":"0x1f7d7550b1b028f7571e69a784071f0205fd2efa","result_hash":"bf7614e6e838b22e4363dfcb3022451641875235ca13e64f8d2d8c3334ff85f3","slot":null},{"block":null,"method":"eth_call","params":["0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","fee()"],"raw_result":"500","result_hash":"5ac95f46dcda9e6a85f4d281cd691aea7b00846d8f8612d198d396136e9c5140","slot":null},{"block":null,"method":"eth_call","params":["0x1f7d7550B1b028f7571E69A784071F0205FD2EfA","getPool","0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168","0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","0x1f4"],"raw_result":"0xd4eb21209c4d6093f80b5b84f5c45cc093ea14a3","result_hash":"b1a9e13a2ab4a76970bf55ffdd7ba947f2ba247944d56ac588128fc57ad994a5","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","0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3"],"raw_result":"Some(\"504150197752\")","result_hash":"f0d7906fef51e17d5c3ff87e85ff0a3aa69846548182aaf1c2eaf8f8278a1c55","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","symbol()"],"raw_result":"Some(\"NVDA\")","result_hash":"021d1642ab9caf5c93ff501b70a3d5285343a63f3b632bcbe7daed2fdac7ebfb","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","balanceOf","0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3"],"raw_result":"Some(\"11877109264683094459350\")","result_hash":"ea0d2d1458f634b9e2ce9128c235ad04879928e7381e7b22001c5719217e3449","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(\"696466203018141\")","result_hash":"9e0dd73d8665999ee170ecc02f65a726e81cb0667b638dd2df3292428e09ed98","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","symbol()"],"raw_result":"Some(\"NVDA\")","result_hash":"021d1642ab9caf5c93ff501b70a3d5285343a63f3b632bcbe7daed2fdac7ebfb","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","name()"],"raw_result":"Some(\"NVIDIA • Robinhood Token\")","result_hash":"164300b6b2737c6d4c2f7641a7df85a5a7adae8429019a4b66cdf2e8e5fe57c6","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","totalSupply()"],"raw_result":"Some(\"90148061024320000000000\")","result_hash":"383fa8ab5095698afa27dd9ee3d17aff99f82a8ac4bf884b0885030b16a6fe8b","slot":null},{"block":null,"method":"eth_call","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","uiMultiplier()"],"raw_result":"1000775159164630595","result_hash":"52e5ec7fbc2c3245d93278c80d04f4f9d203a2a2284a006b4b2e708b84182d87","slot":null},{"block":null,"method":"eth_getCode","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","latest"],"result_hash":"e023f4a2e14683cf62969bf3dc7d7821b1e293e30ebe17f3bc5fd0b223173f25","slot":null},{"block":null,"method":"eth_getCode","params":["0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","latest"],"result_hash":"e023f4a2e14683cf62969bf3dc7d7821b1e293e30ebe17f3bc5fd0b223173f25","slot":null}],"registry_entry":{"chain":"robinhood","contract":"0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","decimals":18,"issuer":"Robinhood","last_checked":"2026-10-18T18:54:09Z","name":"NVIDIA","official_deployments":[{"address":"0xd0601CE157Db5bdC3162BbaC2a2C8aF5320D9EEC","network":"Robinhood Chain"}],"source":"robinhood-registry","source_url":"https://api.robinhood.com/rhj/assets","ticker":"NVDA"},"registry_hash":"e40a8f7ec2f1a2c1d6467a45e0976602299513549c0406d646df02a3ecb928c8","signer":"GJWKkiUd3zj1pJGfeE7JitiPiwDJC6XmNFvpJWJuvvpn","slot":null,"subject":"0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3","ticker":"NVDA","verdict":{"Verified":{"issuer":"Robinhood","ticker":"NVDA"}},"version":1}

Signature

cMbO6wV/fB1o8qngXH2849zf52ihZdpbG2SFo5EcRyuykmoJtOF1NWef0N0ROoAsl+9HsqgSAhlt9dWna6K/BA==

API call

GET /api/attest/d38c99b5cc248d369ee3943961bf67a8c2b1b1f525eb5ee25611a926668384ac

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.