USDC/MSTRx

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

Canonical JSON

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xStocks","pool":{"base":{"address":"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","balance":"4805374053","decimals":6,"symbol":"USDC"},"chain":"Ethereum","dex":"uniswap-v3","pool":"0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","quote":{"address":"0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","balance":"85411357231422744","decimals":18,"symbol":"MSTRx"}},"quote_share_of_supply":6.421906558753591e-7,"reads":[{"block":null,"method":"eth_getCode","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","latest"],"result_hash":"1c9409806518d1a5f52d79299ea0289ea2ff527e05895cd8f7a36d4cca28a13e","slot":null},{"block":null,"method":"eth_getCode","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","latest"],"result_hash":"1c9409806518d1a5f52d79299ea0289ea2ff527e05895cd8f7a36d4cca28a13e","slot":null},{"block":null,"method":"eth_getCode","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","latest"],"result_hash":"2b71a2847b7013f2ac0ae6a5b4d8e35e6db09804205746fceb515c0771a04380","slot":null},{"block":26100079,"method":"eth_blockNumber","params":[],"result_hash":"6809c9feff758082d73b7a3506b273d144336279105d645aa190185fef3e1c34","slot":null},{"block":null,"method":"eth_call","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","token0()"],"raw_result":"0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48","result_hash":"6239f262cd1d947b947081c9eba6e8771378942478e1d48654f4f132ebb96021","slot":null},{"block":null,"method":"eth_call","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","token1()"],"raw_result":"0xae2f842ef90c0d5213259ab82639d5bbf649b08e","result_hash":"56940f6b2e77902e5c396c4da3010c901b28fa01a562bb3b7e0230205728853a","slot":null},{"block":null,"method":"eth_call","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","getReserves()"],"raw_result":"false","result_hash":"076de6e730df0b4c3860877a0f619c6ac11f8aefd78313ac793a2a703c026869","slot":null},{"block":null,"method":"eth_call","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","slot0()"],"raw_result":"true","result_hash":"18d10c7d2b4b04aaf04254d1ae5d655a5dc0407cbcdd5a8c3986e985370f36ee","slot":null},{"block":null,"method":"eth_call","params":["0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","factory()"],"raw_result":"Some(0x1f98431c8ad98523631ae4a59f267346ea31f984)","result_hash":"9b44ff123ef94b4ea3bad901278f92c6e65288f31af4d3eaff07b493d1a79084","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":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","balanceOf","0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2"],"raw_result":"Some(\"4805374053\")","result_hash":"741083ddb51fc2d25da22b37159d9be65c03958b1119dea5d5c04a7163689e59","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","symbol()"],"raw_result":"Some(\"MSTRx\")","result_hash":"2e3697209176ff64ca5124425c2bdc1299f4b196c997b9ec8657f1305f64c4f1","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","balanceOf","0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2"],"raw_result":"Some(\"85411357231422744\")","result_hash":"4d43292f3953959a2c1f064ba765bf2c57ffb3b003ef000e751b26d00571d0a2","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":"None","result_hash":"f2953d2931e36d0c55640f51865f8394ebe52194765d04e521017232558f871c","slot":null},{"block":null,"method":"eth_call","params":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","totalSupply()"],"raw_result":"Some(\"49063382459565411\")","result_hash":"6f3812a4456e27f0d413e8db7659e272b89c90a697a07b60c7c9b324d144d19f","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","symbol()"],"raw_result":"Some(\"MSTRx\")","result_hash":"2e3697209176ff64ca5124425c2bdc1299f4b196c997b9ec8657f1305f64c4f1","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","name()"],"raw_result":"Some(\"MicroStrategy xStock\")","result_hash":"4965a6154980379f43c8f963046a283a0d87ad0c35ed265ea7d5729424cfb66a","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","decimals()"],"raw_result":"Some(18)","result_hash":"c14f173ff30df32f36fac2ea29d9a20482082428fd32b58be5433d310884f764","slot":null},{"block":null,"method":"eth_call","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","totalSupply()"],"raw_result":"Some(\"133000000000000000000000\")","result_hash":"7029ba7ffb89f0b15ded6e63ca2353b658f1e51dee3e8a2b7abfce870f44acc4","slot":null},{"block":null,"method":"eth_getCode","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null},{"block":null,"method":"eth_getCode","params":["0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","latest"],"result_hash":"71ee049d0c0cab5d785d7aef2e6b591e511475fb8ef465f4d8f5335bfd412bfd","slot":null}],"registry_entry":{"chain":"Ethereum","contract":"0xAE2f842EF90C0d5213259Ab82639D5BBF649b08E","decimals":null,"issuer":"Backed xStocks","last_checked":"2026-10-01T20:57:54Z","name":"MicroStrategy","source":"xstocks-api","source_url":"https://api.xstocks.fi/api/v2/public/assets","ticker":"MSTR"},"registry_hash":"d7f46f786c734c593c08efa928ad8aab2634bf0bae691bfee86ed7837818ced0","signer":"GJWKkiUd3zj1pJGfeE7JitiPiwDJC6XmNFvpJWJuvvpn","slot":null,"subject":"0xde9A4FF448252248D7Bc4F21FD20975FFd5290D2","ticker":"MSTR","verdict":{"Verified":{"issuer":"Backed xStocks","ticker":"MSTR"}},"version":1}

Signature

uqnG15dJavRHIdPeXWWZRYiBf4+HyF/9TApdQz2cC8XuXuI9tldzdK6/TXqsOqHkp5p+e+29fpjYSDItNJAEBQ==

API call

GET /api/attest/befe3f7ce5d0acdb2b3ddd0ef7b8e232aafeca2b8b09b20bd235a939905ac63b

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.