tcf-v2-implementation

IAB TCF v2.2 Implementation

Overview

The IAB Europe Transparency and Consent Framework (TCF) v2.2, released in May 2023 as an update to v2.0, provides a standardized mechanism for collecting, encoding, and distributing user consent signals across the programmatic advertising supply chain. Publishers, advertisers, and ad technology vendors use TCF to communicate consent status through the TC String — a compact, base64url-encoded data structure. TCF v2.2 introduced key changes including the removal of legitimate interest as a legal basis for cross-device targeting (Purpose 2 in part) and restrictions on certain vendor practices.

TCF v2.2 Architecture

Core Components

1. Consent Management Platform (CMP): The user-facing interface that collects consent. Must be registered with IAB Europe and assigned a CMP ID.
2. Global Vendor List (GVL): A centralized registry of ad technology vendors, maintained by IAB Europe, listing each vendor's declared purposes and legal bases.
3. TC String: The encoded consent signal transmitted through the ad supply chain.
4. CMP API (__tcfapi): A JavaScript API that vendors call to read the current consent state.

Implementation for Pinnacle E-Commerce Ltd

Step 1: CMP Registration

Register Pinnacle E-Commerce Ltd's CMP with IAB Europe:

Registration requirements:

• Demonstrate CMP compliance with IAB TCF Policies
• Pass IAB Europe CMP validation testing
• Agree to the CMP Terms and Conditions
• Implement the __tcfapi stub before the full CMP loads

Step 2: Global Vendor List Integration

The GVL is published at https://vendor-list.consensu.org/v3/vendor-list.json and contains:

{
  "gvlSpecificationVersion": 3,
  "vendorListVersion": 287,
  "tcfPolicyVersion": 4,
  "lastUpdated": "2026-03-01T12:00:00Z",
  "purposes": {
    "1": {
      "id": 1,
      "name": "Store and/or access information on a device",
      "description": "Cookies, device or similar online identifiers...",
      "illustrations": ["..."]
    }
  },
  "vendors": {
    "755": {
      "id": 755,
      "name": "Google Advertising Products",
      "purposes": [1, 3, 4],
      "legIntPurposes": [2, 7, 9, 10],
      "flexiblePurposes": [2, 7, 9, 10],
      "specialPurposes": [1, 2],
      "features": [1, 2],
      "specialFeatures": [],
      "policyUrl": "https://policies.google.com/privacy",
      "cookieMaxAgeSeconds": 63072000,
      "usesCookies": true,
      "usesNonCookieAccess": true
    }
  }
}

GVL Management for Pinnacle E-Commerce Ltd:

1. Cache the GVL locally with a maximum staleness of 24 hours
2. Display only vendors that Pinnacle E-Commerce Ltd actually uses (vendor subset)
3. Show vendor count in the consent banner: "We work with 47 advertising partners"
4. Provide a searchable vendor list in the detailed consent layer

Pinnacle E-Commerce Ltd Vendor Subset:

Step 3: TCF v2.2 Purposes

The 11 TCF purposes and their mapping for Pinnacle E-Commerce Ltd:

Special Purposes (always allowed, no consent required):

• SP1: Ensure security, prevent and detect fraud, and fix errors
• SP2: Deliver and present advertising and content

Features (declared, not consented to individually):

• F1: Match and combine data from other data sources
• F2: Link different devices
• F3: Receive and use automatically-sent device characteristics for identification

Special Features (require explicit consent):

• SF1: Use precise geolocation data
• SF2: Actively scan device characteristics for identification

Step 4: TC String Structure

The TC String is a base64url-encoded binary string containing:

Core String Segments:

Vendor Consent Section: Variable-length encoding of per-vendor consent using either a bitfield or range encoding, depending on which is more compact.

Publisher Restrictions Section: Overrides vendor-declared legal bases at the publisher level.

Step 5: Publisher Restrictions

Pinnacle E-Commerce Ltd applies publisher restrictions to enforce consent-only for all purposes:

{
  "publisherRestrictions": [
    {
      "purposeId": 2,
      "restrictionType": 1,
      "vendorIds": [91, 42, 69]
    },
    {
      "purposeId": 7,
      "restrictionType": 1,
      "vendorIds": [91, 42, 69, 253]
    },
    {
      "purposeId": 9,
      "restrictionType": 1,
      "vendorIds": [91, 42, 69]
    },
    {
      "purposeId": 10,
      "restrictionType": 1,
      "vendorIds": [91, 42, 69, 253]
    }
  ]
}

Restriction types:

• 0 = Purpose flatly not allowed by publisher
• 1 = Require consent (override legitimate interest)
• 2 = Require legitimate interest (override consent)
• 3 = Vendor requires both consent and LI to process

Step 6: CMP API Implementation

The __tcfapi must be available before any vendor scripts load:

Stub Implementation (loads first):

(function() {
  var queue = [];
  var tcfapi = function(command, version, callback, parameter) {
    if (command === 'addEventListener') {
      queue.push({ command: command, callback: callback });
    } else {
      queue.push({ command: command, version: version, callback: callback, parameter: parameter });
    }
  };
  tcfapi.queue = queue;
  window.__tcfapi = tcfapi;
})();

Supported Commands:

getTCData Response:

{
  "tcString": "CPyXXYAPyXXYAAGABCENB4CgAP_AAH_AAAAAHfoBpDxkBSFCAGJoYtkgAAAGxwAAICACABAAoAAAABoAIAQAAAAQAAAgBAAAABIAIAIAAABAGEAAAAAAQAAAAQAAAEAAAAAAIQIAAAAAAiBAAAAAAAAAAAAAAABAAAAAAAAAAgAAAAAAAQAA",
  "tcfPolicyVersion": 4,
  "cmpId": 432,
  "cmpVersion": 1,
  "gdprApplies": true,
  "eventStatus": "useractioncomplete",
  "purpose": {
    "consents": { "1": true, "2": false, "3": false, "4": false, "7": true },
    "legitimateInterests": {}
  },
  "vendor": {
    "consents": { "755": true, "91": false, "42": false },
    "legitimateInterests": {}
  },
  "publisher": {
    "restrictions": { "2": { "91": 1, "42": 1, "69": 1 } }
  }
}

TCF v2.2 Compliance Validation

Validation Checklist

Key Legal and Technical References

• IAB Europe TCF v2.2 Technical Specification (May 2023) — TC String format, CMP API, GVL structure
• IAB Europe TCF Policies v4 — Rules governing CMPs and vendors
• IAB Europe CMP Validator Tool — Automated TC String validation
• ePrivacy Directive 2002/58/EC, Article 5(3) — Legal basis for TCF Purpose 1
• CJEU Case C-673/17 (Planet49) — Active consent requirements
• Belgian DPA Decision 21/2022 (IAB Europe) — Found IAB Europe a data controller for TC String; TCF must ensure valid GDPR consent
• GDPR Article 4(11) — Consent definition applicable to TCF consent signals