1.1 Motivation

Traditional paper receipts present numerous challenges including environmental waste, consumer inconvenience, difficult expense tracking, and limited machine readability. While various digital receipt solutions exist, they lack interoperability and standardization, creating fragmented ecosystems where consumers must manage multiple apps and merchants must integrate with numerous proprietary systems.

The Digital Receipt Protocol aims to solve these problems by providing:

• A standardized data format for receipt information
• Secure transmission mechanisms protecting consumer privacy
• Cryptographic verification to prevent fraud
• Flexible discovery and delivery methods
• Support for various transaction types and industries
• Accessibility features for all users

1.2 Scope

This specification covers:

• Core data model for digital receipts
• JSON-LD serialization format
• HTTP-based protocol for receipt transmission
• Security and privacy requirements
• Cryptographic signing and verification
• Discovery mechanisms
• Extension points for industry-specific data

This specification does not cover:

• Payment processing protocols (e.g., payment authorization)
• Point-of-sale system implementations
• Consumer wallet application implementations
• Tax calculation or compliance mechanisms

1.3 Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

Receipt

A digital document that records the details of a commercial transaction.

Merchant

The entity providing goods or services and issuing receipts.

Consumer

The entity purchasing goods or services and receiving receipts.

Receipt Provider

A system that generates and serves digital receipts on behalf of merchants.

Receipt Consumer

An application or service that retrieves and processes digital receipts.

Receipt Identifier

A unique, persistent identifier for a specific receipt.

Receipt Endpoint

A URL where a digital receipt can be retrieved.

2.1 Conformance Classes

This specification defines the following conformance classes:

2.1.1 DRP Receipt Provider

A DRP Receipt Provider must:

• Generate receipts conforming to the data model defined in Section 3
• Serialize receipts using JSON-LD as specified in Section 4
• Implement at least one delivery method from Section 6
• Sign receipts using the mechanism defined in Section 7
• Implement the security requirements in Section 8

2.1.2 DRP Receipt Consumer

A DRP Receipt Consumer must:

• Parse receipts conforming to the JSON-LD format in Section 4
• Verify receipt signatures as specified in Section 7
• Implement at least one discovery method from Section 5
• Handle errors as defined in Section 9

3.1 Overview

The DRP data model is based on Schema.org vocabulary extended with DRP-specific properties. The core entity is the Receipt which contains transaction details, merchant information, line items, payment information, and metadata.

3.2 Receipt Object

The Receipt object is the top-level container for all receipt data.

3.3 LineItem Object

Represents an individual item or service on the receipt.

3.4 Organization (Merchant) Object

3.5 MonetaryAmount Object

3.6 PaymentMethod Object

3.7 TaxAmount Object

3.8 DigitalSignature Object

4.1 Format Requirements

DRP receipts must be serialized as JSON-LD documents. The JSON-LD context must include:

"@context": [
  "https://schema.org",
  "https://www.w3.org/ns/drp/v1"
]

4.2 Complete Example

{
  "@context": [
    "https://schema.org",
    "https://www.w3.org/ns/drp/v1"
  ],
  "@type": "Receipt",
  "receiptId": "urn:uuid:550e8400-e29b-41d4-a716-446655440000",
  "receiptNumber": "TXN-2024-001234",
  "dateIssued": "2024-12-04T14:32:00-06:00",
  "merchant": {
    "@type": "Organization",
    "name": "Acme Electronics Store",
    "taxId": "12-3456789",
    "address": {
      "@type": "PostalAddress",
      "streetAddress": "123 Main Street",
      "addressLocality": "Chicago",
      "addressRegion": "IL",
      "postalCode": "60601",
      "addressCountry": "US"
    },
    "telephone": "+1-312-555-0100",
    "email": "support@acmeelectronics.example",
    "url": "https://acmeelectronics.example"
  },
  "location": {
    "@type": "Place",
    "name": "Acme Electronics - Downtown",
    "address": {
      "@type": "PostalAddress",
      "streetAddress": "123 Main Street",
      "addressLocality": "Chicago",
      "addressRegion": "IL",
      "postalCode": "60601",
      "addressCountry": "US"
    }
  },
  "items": [
    {
      "@type": "LineItem",
      "name": "Wireless Bluetooth Headphones",
      "sku": "WBH-2000-BLK",
      "gtin": "00012345678905",
      "quantity": 1,
      "unitPrice": {
        "@type": "MonetaryAmount",
        "value": 79.99,
        "currency": "USD"
      },
      "totalPrice": {
        "@type": "MonetaryAmount",
        "value": 79.99,
        "currency": "USD"
      },
      "category": "Electronics > Audio > Headphones",
      "warranty": {
        "@type": "Warranty",
        "duration": "P1Y",
        "url": "https://acmeelectronics.example/warranty/WBH-2000"
      }
    },
    {
      "@type": "LineItem",
      "name": "USB-C Cable (2m)",
      "sku": "CBL-USBC-2M",
      "gtin": "00012345678912",
      "quantity": 2,
      "unitPrice": {
        "@type": "MonetaryAmount",
        "value": 12.99,
        "currency": "USD"
      },
      "totalPrice": {
        "@type": "MonetaryAmount",
        "value": 25.98,
        "currency": "USD"
      },
      "category": "Electronics > Accessories > Cables"
    }
  ],
  "subtotal": {
    "@type": "MonetaryAmount",
    "value": 105.97,
    "currency": "USD"
  },
  "tax": [
    {
      "@type": "TaxAmount",
      "name": "Illinois Sales Tax",
      "rate": 6.25,
      "amount": {
        "@type": "MonetaryAmount",
        "value": 6.62,
        "currency": "USD"
      },
      "taxId": "IL-SALES-TAX"
    },
    {
      "@type": "TaxAmount",
      "name": "Chicago Municipal Tax",
      "rate": 1.25,
      "amount": {
        "@type": "MonetaryAmount",
        "value": 1.32,
        "currency": "USD"
      },
      "taxId": "CHI-MUNICIPAL-TAX"
    }
  ],
  "discount": [
    {
      "@type": "Discount",
      "name": "Member Discount",
      "code": "MEMBER10",
      "amount": {
        "@type": "MonetaryAmount",
        "value": -10.60,
        "currency": "USD"
      }
    }
  ],
  "totalPrice": {
    "@type": "MonetaryAmount",
    "value": 103.31,
    "currency": "USD"
  },
  "paymentMethod": {
    "@type": "PaymentCard",
    "name": "Credit Card",
    "cardType": "Visa",
    "lastFourDigits": "4321",
    "authorizationCode": "AUTH123456",
    "transactionId": "TXN-PROC-789012"
  },
  "metadata": {
    "employeeId": "EMP-5678",
    "registerId": "REG-03",
    "receiptUrl": "https://receipts.acmeelectronics.example/550e8400-e29b-41d4-a716-446655440000"
  },
  "signature": {
    "@type": "DigitalSignature",
    "algorithm": "RS256",
    "signatureValue": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
    "publicKey": "https://receipts.acmeelectronics.example/.well-known/jwks.json",
    "created": "2024-12-04T14:32:05-06:00",
    "nonce": "a3f2b1c9d8e7"
  }
}

4.3 Extensions

Implementations may extend the data model with additional properties for industry-specific needs. Extensions should use namespaced property names to avoid conflicts.

{
  "@context": [
    "https://schema.org",
    "https://www.w3.org/ns/drp/v1",
    {
      "restaurant": "https://example.org/restaurant-extension#"
    }
  ],
  "@type": "Receipt",
  "receiptId": "urn:uuid:123e4567-e89b-12d3-a456-426614174000",
  "restaurant:tableNumber": "42",
  "restaurant:serverName": "Jane Smith",
  "restaurant:partySize": 4,
  "tip": {
    "@type": "MonetaryAmount",
    "value": 15.00,
    "currency": "USD"
  }
}

5.1 Overview

Receipt discovery enables consumers to locate and retrieve digital receipts. DRP defines multiple discovery mechanisms to accommodate different use cases.

5.2 QR Code Discovery

Merchants may provide QR codes containing receipt URLs.

5.2.1 QR Code Format

The QR code must encode a URL in the following format:

https://receipts.example.com/r/{receiptId}?v=1&h={hash}

Where:

• {receiptId}: Unique receipt identifier
• v: Protocol version
• h: Optional integrity hash (SHA-256 of receipt data)

5.3 Email-based Discovery

Receipt providers may send receipts via email containing:

• HTML representation with embedded JSON-LD
• Link to receipt endpoint
• Attached receipt file (.drp extension recommended)

<html>
  <head>
    <script type="application/ld+json">
    {
      "@context": ["https://schema.org", "https://www.w3.org/ns/drp/v1"],
      "@type": "Receipt",
      ...
    }
    </script>
  </head>
  <body>
    <h1>Your Receipt from Acme Electronics</h1>
    <p><a href="https://receipts.acmeelectronics.example/550e8400">
      View Digital Receipt
    </a></p>
  </body>
</html>

5.4 NFC-based Discovery

For NFC-enabled devices, merchants may provide NFC tags containing receipt URLs using NDEF format.

NDEF Record:
  TNF: Well Known
  Type: U (URI)
  Payload: https://receipts.example.com/r/{receiptId}

5.5 Digital Wallet Integration

Payment systems may include receipt endpoints in payment authorization responses, enabling automatic receipt delivery to consumer wallets.

5.6 Well-Known URI

Receipt providers should publish their receipt service metadata at:

https://example.com/.well-known/drp-config.json

{
  "version": "1.0",
  "issuer": "https://receipts.acmeelectronics.example",
  "receiptEndpoint": "https://receipts.acmeelectronics.example/api/receipts",
  "jwksUri": "https://receipts.acmeelectronics.example/.well-known/jwks.json",
  "supportedFormats": ["application/ld+json", "application/pdf"],
  "features": ["digital-signature", "search", "archival"],
  "privacyPolicy": "https://acmeelectronics.example/privacy",
  "termsOfService": "https://acmeelectronics.example/terms"
}

6.1 HTTP-based Retrieval

Receipt providers must support HTTP GET requests to retrieve receipts.

6.1.1 Request Format

GET /api/receipts/{receiptId} HTTP/1.1
Host: receipts.example.com
Accept: application/ld+json
Authorization: Bearer {access_token}
DRP-Version: 1.0

6.1.2 Response Format

HTTP/1.1 200 OK
Content-Type: application/ld+json
Cache-Control: private, max-age=31536000
ETag: "550e8400-e29b-41d4-a716-446655440000-v1"

{
  "@context": ["https://schema.org", "https://www.w3.org/ns/drp/v1"],
  "@type": "Receipt",
  ...
}

6.1.3 Headers

*Required for non-public receipts

6.2 Push Delivery

Receipt providers may support push delivery via webhooks.

6.2.1 Webhook Registration

POST /api/webhooks HTTP/1.1
Host: receipts.example.com
Content-Type: application/json
Authorization: Bearer {access_token}

{
  "url": "https://consumer-app.example/webhooks/receipts",
  "events": ["receipt.created", "receipt.updated"],
  "secret": "webhook_secret_key"
}

6.2.2 Webhook Delivery

POST /webhooks/receipts HTTP/1.1
Host: consumer-app.example
Content-Type: application/ld+json
X-DRP-Event: receipt.created
X-DRP-Signature: sha256=d8f2a1c3b4e5...

{
  "@context": ["https://schema.org", "https://www.w3.org/ns/drp/v1"],
  "@type": "Receipt",
  ...
}

6.3 Batch Retrieval

Implementations may support batch receipt retrieval for efficiency.

POST /api/receipts/batch HTTP/1.1
Host: receipts.example.com
Content-Type: application/json
Authorization: Bearer {access_token}

{
  "receiptIds": [
    "550e8400-e29b-41d4-a716-446655440000",
    "660e8400-e29b-41d4-a716-446655440001"
  ]
}

HTTP/1.1 200 OK
Content-Type: application/json

{
  "receipts": [
    { "@type": "Receipt", ... },
    { "@type": "Receipt", ... }
  ]
}

6.4 Receipt Search

Receipt providers should support search capabilities.

GET /api/receipts?merchant=acme&from=2024-01-01&to=2024-12-31&minAmount=50 HTTP/1.1
Host: receipts.example.com
Authorization: Bearer {access_token}

HTTP/1.1 200 OK
Content-Type: application/json

{
  "receipts": [...],
  "totalResults": 42,
  "nextPage": "https://receipts.example.com/api/receipts?page=2&..."
}

7.1 Signature Requirements

All receipts must be digitally signed by the issuing merchant or receipt provider. Signatures prevent tampering and enable verification of receipt authenticity.

7.2 Supported Algorithms

Implementations must support at least one of:

• RS256: RSA signature with SHA-256 (RECOMMENDED)
• ES256: ECDSA using P-256 curve and SHA-256
• PS256: RSA PSS signature with SHA-256

7.3 Signing Process

1. Create the complete receipt JSON-LD document without the signature field
2. Canonicalize the JSON using JSON Canonicalization Scheme (JCS, RFC 8785)
3. Compute the hash of the canonicalized document (SHA-256)
4. Sign the hash using the private key
5. Encode the signature in Base64
6. Add the signature object to the receipt

// 1. Prepare receipt without signature
const receipt = {
  "@context": [...],
  "@type": "Receipt",
  "receiptId": "...",
  // ... other fields
};

// 2. Canonicalize
const canonical = canonicalize(receipt);

// 3. Hash
const hash = sha256(canonical);

// 4. Sign
const signature = sign(hash, privateKey, "RS256");

// 5. Encode
const signatureValue = base64encode(signature);

// 6. Add signature
receipt.signature = {
  "@type": "DigitalSignature",
  "algorithm": "RS256",
  "signatureValue": signatureValue,
  "publicKey": "https://receipts.example.com/.well-known/jwks.json",
  "created": new Date().toISOString(),
  "nonce": generateNonce()
};

7.4 Verification Process

1. Extract the signature object from the receipt
2. Remove the signature field from the receipt
3. Canonicalize the remaining receipt data
4. Compute the hash (SHA-256)
5. Retrieve the public key from the specified location
6. Verify the signature against the hash
7. Check signature timestamp is reasonable (not too old or in future)

7.5 Public Key Distribution

Receipt providers must publish public keys using JSON Web Key Set (JWKS) format at a well-known URL.

GET /.well-known/jwks.json HTTP/1.1
Host: receipts.example.com

HTTP/1.1 200 OK
Content-Type: application/json

{
  "keys": [
    {
      "kty": "RSA",
      "use": "sig",
      "kid": "2024-12-key-1",
      "n": "xGOr-H7A-D...",
      "e": "AQAB",
      "alg": "RS256"
    }
  ]
}

7.6 Key Rotation

Receipt providers should rotate signing keys periodically (recommended: annually). Old public keys must remain available for historical receipt verification.

8.1 Personal Information Protection

Receipt providers must minimize collection and storage of personally identifiable information (PII). The customer field should only be included when explicitly requested or required for business purposes.

8.2 Access Control

Receipt endpoints must implement authentication and authorization:

• Public receipts: Accessible via URL without authentication (use for public transactions)
• Private receipts: Require OAuth 2.0 bearer token or equivalent

8.2.1 OAuth 2.0 Integration

GET /api/receipts/550e8400-e29b-41d4-a716-446655440000 HTTP/1.1
Host: receipts.example.com
Authorization: Bearer eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...

8.3 Data Retention

Receipt providers should establish clear retention policies. Consumers must have the ability to:

• Request deletion of their receipt data
• Export their receipt history in machine-readable format
• Revoke access to third-party receipt consumers

8.4 Transport Security

All receipt transmissions must use TLS 1.2 or higher. Receipt endpoints must not accept unencrypted HTTP connections.

8.5 Anonymization

For analytics or aggregated reporting, receipt providers should anonymize data by:

• Removing or hashing customer identifiers
• Truncating payment method details
• Generalizing location data

8.6 GDPR and Privacy Regulations

Receipt providers operating in jurisdictions with data protection regulations must comply with applicable laws including:

• Right to access
• Right to erasure ("right to be forgotten")
• Right to data portability
• Privacy by design and default

9.1 HTTP Status Codes

9.2 Error Response Format

Error responses should include a JSON body with details:

HTTP/1.1 404 Not Found
Content-Type: application/json

{
  "error": {
    "code": "receipt_not_found",
    "message": "Receipt with ID '550e8400-e29b-41d4-a716-446655440000' was not found",
    "details": {
      "receiptId": "550e8400-e29b-41d4-a716-446655440000",
      "timestamp": "2024-12-04T14:32:00Z"
    },
    "documentationUrl": "https://docs.drp.example/errors/receipt_not_found"
  }
}

9.3 Validation Errors

For validation failures, include field-specific error details:

{
  "error": {
    "code": "validation_error",
    "message": "Receipt validation failed",
    "validationErrors": [
      {
        "field": "totalPrice.value",
        "message": "Total price does not match sum of line items",
        "expected": 103.31,
        "actual": 100.00
      },
      {
        "field": "signature.algorithm",
        "message": "Unsupported signature algorithm",
        "provided": "HS256",
        "supported": ["RS256", "ES256", "PS256"]
      }
    ]
  }
}

10.1 Language Support

Receipt text content should be provided in the consumer's preferred language when available. Use the Accept-Language HTTP header for language negotiation.

GET /api/receipts/550e8400 HTTP/1.1
Accept-Language: es-MX, es;q=0.9, en;q=0.8

10.2 Localized Content

Implementations may use JSON-LD language maps for multilingual content:

{
  "@type": "LineItem",
  "name": {
    "@value": "Audífonos Bluetooth Inalámbricos",
    "@language": "es"
  },
  "name": {
    "@value": "Wireless Bluetooth Headphones",
    "@language": "en"
  }
}

10.3 Currency and Formatting

All monetary amounts must include ISO 4217 currency codes. Display formatting should follow locale conventions but storage uses standardized decimal representation.

10.4 Date and Time

All timestamps must use ISO 8601 format with timezone information:

"dateIssued": "2024-12-04T14:32:00-06:00"

11.1 Accessibility Requirements

Receipt presentations (web views, apps, etc.) must conform to WCAG 2.1 Level AA guidelines:

• Provide text alternatives for images
• Ensure sufficient color contrast
• Support keyboard navigation
• Provide semantic HTML structure
• Support screen readers

11.2 Alternative Formats

Receipt providers should offer receipts in multiple formats:

• JSON-LD (machine-readable)
• HTML (human-readable, accessible)
• PDF (printable, archival)
• Plain text (simple devices)

GET /api/receipts/550e8400 HTTP/1.1
Accept: text/html

HTTP/1.1 200 OK
Content-Type: text/html

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Receipt - Acme Electronics</title>
  </head>
  <body>
    <main role="main">
      <h1>Receipt</h1>
      ...
    </main>
  </body>
</html>

12.1 Custom Properties

Implementations may add custom properties using namespaced names. Custom properties should use reverse domain notation or explicit context URLs.

{
  "@context": [
    "https://schema.org",
    "https://www.w3.org/ns/drp/v1",
    {
      "acme": "https://acmeelectronics.example/receipt-extension#"
    }
  ],
  "acme:loyaltyPoints": 150,
  "acme:rewardsProgram": "Gold Member"
}

12.2 Industry Extensions

Industry-specific extensions may define additional types and properties. Common extensions include:

• Restaurant Extension: Table number, server info, meal period
• Hotel Extension: Room number, check-in/out dates, guest services
• Healthcare Extension: Insurance details, prescription info, provider codes
• Transportation Extension: Route, vehicle, fare class

13.1 Media Type Registration

This specification registers the following media type:

Type name:

application

Subtype name:

drp+json

Required parameters:

None

Optional parameters:

version (default: "1.0")

Encoding considerations:

UTF-8

Security considerations:

See Section 8 of this specification

Interoperability considerations:

This format extends JSON-LD and is compatible with JSON-LD processors

Published specification:

This document

Applications that use this media type:

Digital receipt systems, expense management applications, accounting software

13.2 Well-Known URI Registration

This specification registers the following well-known URI:

URI suffix:

drp-config.json

Change controller:

W3C

Specification document:

This document, Section 5.6

Related information:

None

14.1 Restaurant Receipt

{
  "@context": ["https://schema.org", "https://www.w3.org/ns/drp/v1"],
  "@type": "Receipt",
  "receiptId": "urn:uuid:789e4567-e89b-12d3-a456-426614174000",
  "receiptNumber": "TABLE-42-2024-1204",
  "dateIssued": "2024-12-04T19:45:00-06:00",
  "merchant": {
    "@type": "Restaurant",
    "name": "The Blue Bistro",
    "address": {
      "@type": "PostalAddress",
      "streetAddress": "456 Oak Avenue",
      "addressLocality": "Chicago",
      "addressRegion": "IL",
      "postalCode": "60614",
      "addressCountry": "US"
    }
  },
  "items": [
    {
      "@type": "LineItem",
      "name": "Caesar Salad",
      "quantity": 2,
      "unitPrice": {"@type": "MonetaryAmount", "value": 12.00, "currency": "USD"},
      "totalPrice": {"@type": "MonetaryAmount", "value": 24.00, "currency": "USD"}
    },
    {
      "@type": "LineItem",
      "name": "Grilled Salmon",
      "quantity": 1,
      "unitPrice": {"@type": "MonetaryAmount", "value": 28.00, "currency": "USD"},
      "totalPrice": {"@type": "MonetaryAmount", "value": 28.00, "currency": "USD"}
    },
    {
      "@type": "LineItem",
      "name": "House Wine (Glass)",
      "quantity": 2,
      "unitPrice": {"@type": "MonetaryAmount", "value": 9.00, "currency": "USD"},
      "totalPrice": {"@type": "MonetaryAmount", "value": 18.00, "currency": "USD"}
    }
  ],
  "subtotal": {"@type": "MonetaryAmount", "value": 70.00, "currency": "USD"},
  "tax": [{
    "@type": "TaxAmount",
    "name": "Sales Tax",
    "rate": 10.25,
    "amount": {"@type": "MonetaryAmount", "value": 7.18, "currency": "USD"}
  }],
  "tip": {"@type": "MonetaryAmount", "value": 14.00, "currency": "USD"},
  "totalPrice": {"@type": "MonetaryAmount", "value": 91.18, "currency": "USD"},
  "paymentMethod": {
    "@type": "PaymentCard",
    "cardType": "Mastercard",
    "lastFourDigits": "5678"
  },
  "metadata": {
    "tableNumber": "42",
    "serverName": "Maria Garcia",
    "partySize": 2
  },
  "signature": {
    "@type": "DigitalSignature",
    "algorithm": "RS256",
    "signatureValue": "eyJhbGc...",
    "publicKey": "https://receipts.bluebistro.example/.well-known/jwks.json",
    "created": "2024-12-04T19:46:00-06:00"
  }
}

14.2 Subscription Service Receipt

{
  "@context": ["https://schema.org", "https://www.w3.org/ns/drp/v1"],
  "@type": "Receipt",
  "receiptId": "urn:uuid:890e4567-e89b-12d3-a456-426614174000",
  "receiptNumber": "SUB-2024-DEC-123456",
  "dateIssued": "2024-12-01T00:00:00Z",
  "merchant": {
    "@type": "Organization",
    "name": "StreamFlix Media Services",
    "url": "https://streamflix.example"
  },
  "items": [{
    "@type": "LineItem",
    "name": "Premium Plan - Monthly Subscription",
    "quantity": 1,
    "unitPrice": {"@type": "MonetaryAmount", "value": 15.99, "currency": "USD"},
    "totalPrice": {"@type": "MonetaryAmount", "value": 15.99, "currency": "USD"},
    "metadata": {
      "subscriptionId": "sub_1234567890",
      "billingPeriod": "2024-12-01/2025-01-01",
      "autoRenew": true,
      "nextBillingDate": "2025-01-01"
    }
  }],
  "totalPrice": {"@type": "MonetaryAmount", "value": 15.99, "currency": "USD"},
  "paymentMethod": {
    "@type": "PaymentCard",
    "cardType": "Visa",
    "lastFourDigits": "1234"
  },
  "signature": {
    "@type": "DigitalSignature",
    "algorithm": "ES256",
    "signatureValue": "MEUCIQD...",
    "publicKey": "https://api.streamflix.example/.well-known/jwks.json",
    "created": "2024-12-01T00:00:05Z"
  }
}

15.1 Normative References

[RFC2119]

Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.

[RFC8259]

Bray, T., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, December 2017.

[RFC8785]

Rundgren, A., Jordan, B., and S. Erdtman, "JSON Canonicalization Scheme (JCS)", RFC 8785, June 2020.

[JSON-LD]

Sporny, M., Longley, D., Kellogg, G., Lanthaler, M., Lindström, N., "JSON-LD 1.1", W3C Recommendation, July 2020.

[SCHEMA-ORG]

Schema.org, "Schema.org - Schema.org", https://schema.org/

[ISO4217]

ISO 4217:2015, "Codes for the representation of currencies"

[ISO8601]

ISO 8601:2019, "Date and time — Representations for information interchange"

15.2 Informative References

[OAUTH2]

Hardt, D., "The OAuth 2.0 Authorization Framework", RFC 6749, October 2012.

[WCAG21]

Kirkpatrick, A., Connor, J., Campbell, A., Cooper, M., "Web Content Accessibility Guidelines (WCAG) 2.1", W3C Recommendation, June 2018.

[GDPR]

EU General Data Protection Regulation (GDPR), Regulation (EU) 2016/679

[RFC7515]

Jones, M., Bradley, J., Sakimura, N., "JSON Web Signature (JWS)", RFC 7515, May 2015.

[RFC7517]

Jones, M., "JSON Web Key (JWK)", RFC 7517, May 2015.