{
  "@context": [
    "https://letterprove.com/ns/attestation/v1",
    "https://schema.org"
  ],
  "id": "att_wagebase_ca454cb6",
  "type": "LetterproveAttestation",
  "schemaVersion": "1.1",
  "attestationKind": "customer-usage",
  "environment": "demonstration",
  "issuer": {
    "name": "Letterprove",
    "id": "did:web:letterprove.com",
    "url": "https://letterprove.com",
    "service": "Independent usage-attestation service"
  },
  "subject": {
    "name": "Wagebase",
    "domain": "wagebase.com",
    "url": "https://wagebase.com",
    "category": "Payroll & People Platform"
  },
  "relationship": {
    "type": "third-party",
    "keyCustody": "In production: segregated, HSM-backed issuer key held arm's-length from the subject. This demonstration uses a demo key.",
    "disclosure": "Letterprove is the independent attestation service; in production it operates arm's-length from the subject with segregated key custody. Participating customers grant read-only, scoped access; Letterprove reads usage counters (seats, activity, tenure) — never customer content — and signs the result. This is a demonstration: the subject and customer identities are illustrative and the signing key is a demo key."
  },
  "issuedAt": "2026-08-06T17:00:00Z",
  "expiresAt": "2026-11-04T17:00:00Z",
  "status": "active",
  "coverage": {
    "customersShown": 8,
    "totalCustomers": 236,
    "shownRepresentTopPercent": 10,
    "percentileMetric": "seats",
    "consentRatePercent": 91,
    "disclosure": "The 8 named customers represent the top 10% of Wagebase's accounts by seats. 91% of all paying customers consented to independent usage attestation."
  },
  "customers": [
    {
      "company": "Cardinal Trust Bank",
      "industry": "Financial Services",
      "plan": "Enterprise",
      "activeSeats": 3140,
      "monthsActive": 29,
      "outcome": "-52% payroll cycle time",
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Helix Biosciences",
      "industry": "Life Sciences",
      "plan": "Enterprise",
      "activeSeats": 1880,
      "monthsActive": 21,
      "outcome": "-38% payroll error rate",
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Atlas Freight Systems",
      "industry": "Logistics & Transportation",
      "plan": "Enterprise",
      "activeSeats": 2460,
      "monthsActive": 24,
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Everline Insurance",
      "industry": "Insurance",
      "plan": "Enterprise",
      "activeSeats": 1520,
      "monthsActive": 33,
      "outcome": "-61% off-cycle corrections",
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Meridian Retail Holdings",
      "industry": "Retail",
      "plan": "Business",
      "activeSeats": 940,
      "monthsActive": 16,
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Verdant Energy Group",
      "industry": "Energy & Utilities",
      "plan": "Enterprise",
      "activeSeats": 2110,
      "monthsActive": 26,
      "outcome": "-44% manual reconciliation hours",
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Kestrel Semiconductors",
      "industry": "Manufacturing",
      "plan": "Enterprise",
      "activeSeats": 1670,
      "monthsActive": 13,
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    },
    {
      "company": "Summit Public University System",
      "industry": "Higher Education",
      "plan": "Enterprise",
      "activeSeats": 1290,
      "monthsActive": 19,
      "outcome": "2.3x faster multi-state onboarding",
      "status": "verified",
      "verifiedVia": "customer-authorized read-only usage attestation"
    }
  ],
  "aggregate": [
    {
      "label": "Annualized payroll processed across attested accounts",
      "value": "$4.7B+"
    },
    {
      "label": "Employees and contractors paid per cycle across attested accounts",
      "value": "1.2M+"
    },
    {
      "label": "On-time, penalty-free filing rate across attested accounts",
      "value": "99.94%"
    }
  ],
  "signatureMeaning": "A valid Ed25519 signature proves this record was issued by Letterprove (key at did:web:letterprove.com) and has not been altered. Each named customer consented and was verified via read-only usage attestation.",
  "methodology": {
    "summary": "Each participating customer grants Letterprove a read-only, scoped token. Letterprove reads usage counters (active seats, activity, tenure) and, where the customer opts in, an outcome metric — never customer content. Figures are canonicalized (RFC 8785 JCS), hashed (SHA-256) and signed with a domain-bound Ed25519 key. The coverage block discloses exactly how representative the shown sample is.",
    "principles": [
      "Named customers consented to be attested.",
      "Read-only usage counters — never customer content.",
      "Coverage percentile disclosed — no cherry-picking hidden.",
      "Signed and independently verifiable — verify, don't trust."
    ]
  },
  "verification": {
    "signatureAlgorithm": "Ed25519",
    "proofType": "JcsEd25519Signature2026",
    "canonicalization": "RFC 8785 JCS (sorted keys, UTF-8, no whitespace)",
    "digestAlgorithm": "SHA-256",
    "didDocumentUrl": "https://letterprove.com/.well-known/did.json",
    "jwksUrl": "https://letterprove.com/.well-known/letterprove/jwks.json",
    "verificationMethod": "did:web:letterprove.com#key-1"
  },
  "proof": {
    "type": "JcsEd25519Signature2026",
    "created": "2026-08-06T17:00:00Z",
    "verificationMethod": "did:web:letterprove.com#key-1",
    "canonicalization": "RFC 8785 JCS (sorted keys, UTF-8, no whitespace)",
    "digestAlgorithm": "SHA-256",
    "digestValue": "0EWyzgwi28tHF2hAqI30YT7Tf9RVwLIVXhBDWWswA7A",
    "signatureAlgorithm": "Ed25519",
    "publicKeyHex": "e814af319722acde1f401985342e85ab26147291546d0934efe632a3c72ec954",
    "publicKeyMultibase": "z6Mkv5CvaxbaD1RuJoY9nZ2YZDbteEjY7TALHahXuVf6Jibd",
    "signatureValue": "IL0QRBcYbPJQJX8Y4nV1vEsRfhDiUmBrOvDQOaB0w-F9ZX1cJdZ74A26PvogcMbnJhWl6nW29DH7ltTcLIjIAQ"
  }
}