Does AAPLx / USDC 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":26235002,"chain":"ethereum","checked_at":"2026-10-20T16:30:17Z","dev":false,"expires_at":"2026-10-21T16:30:17Z","issuer":"Backed xStocks","pool":{"base":{"address":"0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","balance":"978067401133635562","decimals":18,"symbol":"AAPLx"},"chain":"ethereum","dex":"uniswap-v4","pool":"0x2cece44ca1b3c4fab24624205e526b4bcf6b2f1aeff9d0fb0c535e19ba6106ce","quote":{"address":"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","balance":"7074958","decimals":6,"symbol":"USDC"}},"quote_share_of_supply":0.000013191329303697644,"reads":[{"block":null,"method":"eth_call","params":["0xbd216513d74c8cf14cf4747e6aaa6420ff64ee9e","poolKeys","0x2cece44ca1b3c4fab24624205e526b4bcf6b2f1aeff9d0fb0c"],"raw_result":"Object {\"currency0\": String(\"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a\"), \"currency1\": String(\"0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48\"), \"fee\": String(\"996300\"), \"hooks\": String(\"0x0000000000000000000000000000000000000000\"), \"tickSpacing\": String(\"19926\")}","result_hash":"442879ee0916a590f84cb7aa739e82fd9a514bbcb13e4e40907f7120f3110acf","slot":null},{"block":null,"method":"eth_call","params":["0x7ffe42c4a5deea5b0fec41c94c136cf115597227","getSlot0","0x2cece44ca1b3c4fab24624205e526b4bcf6b2f1aeff9d0fb0c535e19ba6106ce"],"raw_result":"true","result_hash":"18d10c7d2b4b04aaf04254d1ae5d655a5dc0407cbcdd5a8c3986e985370f36ee","slot":null},{"block":null,"method":"eth_call","params":["0x7ffe42c4a5deea5b0fec41c94c136cf115597227","getLiquidity","0x2cece44ca1b3c4fab24624205e526b4bcf6b2f1aeff9d0fb0c535e19ba6106ce"],"raw_result":"2630548756867","result_hash":"51270c426911fed82989d82dcc90f398043b361174fc6f6eb552570d6a6ced53","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","symbol()"],"raw_result":"Some(\"AAPLx\")","result_hash":"c700afc7f6ded90a1d2ffbe8bc821567ee617c777989a05562bdcff3f0f4f731","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","symbol()"],"raw_result":"Some(\"USDC\")","result_hash":"a3c9e246b0832b52e41efce041d8614251f5e288cdd4b192e85bfd3dfcb748ff","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","decimals()"],"raw_result":"Some(6)","result_hash":"c68fe6989b1835302197d0af5be845dfab10ed9f9632205eb4ab5b949b9e1a6a","slot":null},{"block":26235002,"method":"eth_blockNumber","params":[],"result_hash":"53fde1578e10bb4eeb7dda77a1f886eca5ef356db24072ae2acd8a9ba342c6ad","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","symbol()"],"raw_result":"Some(\"USDC\")","result_hash":"a3c9e246b0832b52e41efce041d8614251f5e288cdd4b192e85bfd3dfcb748ff","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","name()"],"raw_result":"Some(\"USD Coin\")","result_hash":"fe94af15dc887a2c9df1fb0d6d276e6c586ca9d430ffeac0d05e4baee0637fd1","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","decimals()"],"raw_result":"Some(6)","result_hash":"c68fe6989b1835302197d0af5be845dfab10ed9f9632205eb4ab5b949b9e1a6a","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","totalSupply()"],"raw_result":"Some(\"47795391877248347\")","result_hash":"852606b4ef47d2e7c4e727c588fb119ad5428befd268c170ed8043cd3308a644","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","symbol()"],"raw_result":"Some(\"AAPLx\")","result_hash":"c700afc7f6ded90a1d2ffbe8bc821567ee617c777989a05562bdcff3f0f4f731","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","name()"],"raw_result":"Some(\"Apple xStock\")","result_hash":"38558e23e8582c8a29fab99f3c180b0d4dfe6162231fc0aee4206b8a94c1926f","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","totalSupply()"],"raw_result":"Some(\"74144718747903202410949\")","result_hash":"81f6a20a09014db1b929586aff07b1b5961037358c71feb59239f0a9da21c628","slot":null},{"block":null,"method":"eth_getCode","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null},{"block":null,"method":"eth_getCode","params":["0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null}],"registry_entry":{"chain":"ethereum","contract":"0x9d275685dC284C8eB1C79f6ABA7a63Dc75ec890a","decimals":null,"issuer":"Backed xStocks","last_checked":"2026-10-20T15:40:19Z","name":"Apple","official_deployments":[{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Ethereum","wrapper_address":"0x5aa7649fdbda47de64a07ac81d64b682af9c0724","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"BinanceSmartChain","wrapper_address":"0x5aa7649fdbda47de64a07ac81d64b682af9c0724","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Arbitrum","wrapper_address":"0x5aa7649fdbda47de64a07ac81d64b682af9c0724","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"XsbEhLAtcf6HdfpFZ5xEMdqW8nfAvcsP5bdudRLJzJp","network":"Solana"},{"address":"TZ7nsyCuQq1cusCtex6V4qbzWcb3NbibAM","network":"Tron"},{"address":"EQDsjAwfKo-6FVZv2EYt-1CaZTY_ZL-pfkSId6jeQchNwmdo","network":"Ton"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Mantle","wrapper_address":"0x5aa7649fdbda47de64a07ac81d64b682af9c0724","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"HyperEVM"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Ink","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"XLayer","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Optimism","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"},{"address":"0x9d275685dc284c8eb1c79f6aba7a63dc75ec890a","network":"Monad","wrapper_address_v2":"0x943bf64d566c32a2bcd41ac92fb63c111cc9de8f"}],"source":"xstocks-api","source_url":"https://api.xstocks.fi/api/v2/public/assets","ticker":"AAPL"},"registry_hash":"e42f41f1e0f0dc698c2f40aa64c9df099fb8b38e10dd3a1a8d6c92b85ad7aedb","signer":"GJWKkiUd3zj1pJGfeE7JitiPiwDJC6XmNFvpJWJuvvpn","slot":null,"subject":"0x2cece44ca1b3c4fab24624205e526b4bcf6b2f1aeff9d0fb0c535e19ba6106ce","ticker":"AAPL","verdict":{"Verified":{"issuer":"Backed xStocks","ticker":"AAPL"}},"version":1}

Signature

bFJuNPhvWVCvM+lab/uE9h+Lkm5bhOsyUJgT/R6Rpzupzqn2mpp3qrdeDq2ATAippW2MO+WPndpAjkmH3iXyBQ==

API call

GET /api/attest/c5d81e8d614c7d0ffc8ece7e40cbe99669e67597338265bd501dd62b21e31e8c

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.