Does TBLLx / 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":26282261,"chain":"ethereum","checked_at":"2026-10-27T06:31:08Z","dev":false,"expires_at":"2026-10-28T06:31:08Z","issuer":"Backed xStocks","pool":{"base":{"address":"0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","balance":"1011843793053558396","decimals":18,"symbol":"TBLLx"},"chain":"ethereum","dex":"uniswap-v4","pool":"0x18459de4e0f701748fc1d4f2dbbbb2b21359bd943ce191c266205f821b891b91","quote":{"address":"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","balance":"2000154","decimals":6,"symbol":"USDC"}},"quote_share_of_supply":2.086851025673963e-7,"reads":[{"block":null,"method":"eth_call","params":["0xbd216513d74c8cf14cf4747e6aaa6420ff64ee9e","poolKeys","0x18459de4e0f701748fc1d4f2dbbbb2b21359bd943ce191c266"],"raw_result":"Object {\"currency0\": String(\"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b\"), \"currency1\": String(\"0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48\"), \"fee\": String(\"996261\"), \"hooks\": String(\"0x0000000000000000000000000000000000000000\"), \"tickSpacing\": String(\"19925\")}","result_hash":"5ab043c51f35077a8a853349a2b5fefe13a28cd9a1a6f2d55aeefd23de5885cb","slot":null},{"block":null,"method":"eth_call","params":["0x7ffe42c4a5deea5b0fec41c94c136cf115597227","getSlot0","0x18459de4e0f701748fc1d4f2dbbbb2b21359bd943ce191c266205f821b891b91"],"raw_result":"true","result_hash":"18d10c7d2b4b04aaf04254d1ae5d655a5dc0407cbcdd5a8c3986e985370f36ee","slot":null},{"block":null,"method":"eth_call","params":["0x7ffe42c4a5deea5b0fec41c94c136cf115597227","getLiquidity","0x18459de4e0f701748fc1d4f2dbbbb2b21359bd943ce191c266205f821b891b91"],"raw_result":"1422618860375","result_hash":"dde76d73b61bcaa5f7a304bfd3b29bc88d7c9cc6466285bf35c98ffa364cc454","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","symbol()"],"raw_result":"Some(\"TBLLx\")","result_hash":"48fd2ba4b29fff12935ed2d6049805f3fd8c4dfd8bc8121337b6da40863d9864","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","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":26282261,"method":"eth_blockNumber","params":[],"result_hash":"7bb5b0cde8bb62b0f85e66f1f2ba2af510ac6e2699641e5e9455596388957f17","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(\"47368506913461053\")","result_hash":"943619c0a1f613b7aa3f121a6deffa40d2b590e2ebab702e5c561329c61e8446","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","symbol()"],"raw_result":"Some(\"TBLLx\")","result_hash":"48fd2ba4b29fff12935ed2d6049805f3fd8c4dfd8bc8121337b6da40863d9864","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","name()"],"raw_result":"Some(\"TBLL xStock\")","result_hash":"47096de87d6dd33df1c8d657afce01c3f70dd4c96150a94a8cfb5c44dcb825cc","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","totalSupply()"],"raw_result":"Some(\"4848663275936414330267563\")","result_hash":"622ae741fc0a11a571957366cd7ed8d1726bffd427c707e4c47c156eab79d962","slot":null},{"block":null,"method":"eth_getCode","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null},{"block":null,"method":"eth_getCode","params":["0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null}],"registry_entry":{"chain":"ethereum","contract":"0x4cbf89ED7Bb30b8a860fa86d3c96E9c72931299b","decimals":null,"issuer":"Backed xStocks","last_checked":"2026-10-27T06:07:30Z","name":"TBLL","official_deployments":[{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Ethereum","wrapper_address":"0xcd932bf1c895b7143ec34df5ae7889d3853904d8","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"BinanceSmartChain","wrapper_address":"0xcd932bf1c895b7143ec34df5ae7889d3853904d8","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Arbitrum","wrapper_address":"0xcd932bf1c895b7143ec34df5ae7889d3853904d8","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"XsqBC5tcVQLYt8wqGCHRnAUUecbRYXoJCReD6w7QEKp","network":"Solana"},{"address":"TQRY53VFeCXPAanTYPwCoY4MScdBmXzrNw","network":"Tron"},{"address":"EQCjpympW_XfYPOwuEw39P6wmlk8o6KtRo3kC_6pOVjxANCp","network":"Ton"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Mantle","wrapper_address":"0xcd932bf1c895b7143ec34df5ae7889d3853904d8","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"HyperEVM","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Ink","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"XLayer","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Optimism","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"},{"address":"0x4cbf89ed7bb30b8a860fa86d3c96e9c72931299b","network":"Monad","wrapper_address_v2":"0x461b25b99606fe169d6f0dd6816650ef6536403e"}],"source":"xstocks-api","source_url":"https://api.xstocks.fi/api/v2/public/assets","ticker":"TBLL"},"registry_hash":"bc82dd79029d7e8dfeadd360bed596c6ab53650b30125a41af26f4871fe1cddc","signer":"GJWKkiUd3zj1pJGfeE7JitiPiwDJC6XmNFvpJWJuvvpn","slot":null,"subject":"0x18459de4e0f701748fc1d4f2dbbbb2b21359bd943ce191c266205f821b891b91","ticker":"TBLL","verdict":{"Verified":{"issuer":"Backed xStocks","ticker":"TBLL"}},"version":1}

Signature

ybKZodCTUch4i1q/MpkXK7/uw925pwJYTXlgdYa/E9LSUq7I7TCBzCW05U7+KejIf3FMBrKfS1y5rnX7OWL6AA==

API call

GET /api/attest/284f18de392fe3a78fc8678e2d96f4fd5a87e677955514fc7ab745c38a69fccd

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.