Validate signature certificate chains API

Parse supplied X.509 certificates and check validity windows and issuer links locally. Not a legal trust determination.

The Validate signature certificate chains operation is part of the Electronic Signature & Document Trust API on BRAINIAC.software. Parse supplied X.509 certificates and check validity windows and issuer links locally. Not a legal trust determination. It is exposed as POST /api/v1/document-trust/signature-certificate-chain-validate and priced at $0.04 USDC on Base. Payment uses the x402 exact scheme: an unpaid call returns HTTP 402 with payment requirements; after paying the exact USDC amount, retry the same request with a payment-signature header and Idempotency-Key. No account and no API key are required. Data sources for this product: Caller-supplied PDF bytes, certificates, signers, revocations, and detached signatures Limitations: No commercial electronic-signature platform is used and no API key is required. Technical signature, hash, certificate, and timestamp checks are not a determination of legal enforceability. Full CMS/PKCS#7 verification is reported only when detached signature material is supplied, or ByteRange digests match caller expectations. Revocation is evaluated only against caller-supplied entries. Live commercial OCSP/CRL networks are not queried. Missing signature fields, certificates, and digests are not invented. Outputs are compliance prechecks, drafts, or data lookups for human review. They are not official determinations, legal advice, identity confirmation, or certified filings. Related operations in this group include Verify PDF digital signatures, Validate signature timestamps, Detect signed-document tampering, Check document signature coverage. Open the group documentation for the full request schema, field notes, and response examples before integrating.

POST$0.04 USDC
/api/v1/document-trust/signature-certificate-chain-validate

Example request

curl -i -X POST "https://www.brainiac.software/api/v1/document-trust/signature-certificate-chain-validate" \
  -H 'content-type: application/json' \
  -H 'Idempotency-Key: <fresh-64-character-random-hex-key>' \
  --data-binary @- <<'JSON'
{
  "asOf": "2026-11-04T21:00:00.000Z",
  "certificates": [
    {
      "id": "CERT-1",
      "role": "leaf",
      "documentId": "DOC-1",
      "pem": "-----BEGIN CERTIFICATE-----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\n-----END CERTIFICATE-----\n"
    }
  ]
}
JSON

An unpaid probe returns HTTP 402 with x402 payment requirements. After paying the exact USDC amount on Base, retry the identical request with a payment-signature header.

FAQ

  • Do I need an API key? No. Pay the listed USDC amount with x402.
  • What network? Base (eip155:8453), USDC.
  • Is this an official determination? No. Results are for human review against the cited sources.

Related APIs

Electronic Signature & Document Trust APIFull docsHow it works