TC String bit-level breakdown
Maintained by the Interactive Advertising Bureau (IAB) Europe, the Transparency & Consent Framework (TCF) EU v2 TC String = Core String . Disclosed Vendors . Publisher TC, three segments separated by . and each self-identified by a 3-bit SegmentType (the Core segment has no prefix). It is both the payload of Global Privacy Platform (GPP) §2 and, as a leading-C standalone string, coexists with GPP. Bit-level layout of the 17 Core fields.
- ·Three-segment layout with SegmentType self-identification (0=Core / 1=DisclosedVendors / 3=PublisherTC)
- ·Bit-level table of the 17 Core fields (Version / Created / LastUpdated / CmpId / … / PublisherCC)
Enter chapter→The four declaration families: Purposes / Special Purposes / Features / Special Features
The four declaration families on the Transparency & Consent Framework (TCF) side: Purposes (11 current + 12–24 reserved) / Special Purposes (2) / Features (3) / Special Features (2). Field models differ: Purposes have both Consent and Legitimate Interest (LI) channels, Special Features are Opt-In only.
- ·The current Purposes 1–11 (12–24 reserved), with both Consent and LI channels
- ·Special Purposes 1–2 (SP1 ensure security/prevent fraud/debug, SP2 technically deliver ads or content)
Enter chapter→Publisher Restrictions
partially integratedThe variable-length restriction entries at the tail of the Transparency & Consent Framework (TCF) Core segment: NumPubRestrictions Int(12) + per entry (PurposeId 6 bits + RestrictionType 2 bits + vendor range). The three RestrictionType values: 0 = purpose disallowed / 1 = require consent / 2 = require legitimate interest.
- ·Field layout: NumPubRestrictions Int(12) + per entry PurposeId(6) + RestrictionType(2) + NumEntries + Range
- ·The three-valued semantics of RestrictionType (0/1/2)
Enter chapter→TCF version deltas
partially integratedTransparency & Consent Framework (TCF) version evolution: v1 (deprecated) → v2.0 → v2.1 → v2.2 → v2.3 deltas; v2.4 has no released version and must not be cited as one. The mapping between the TcfPolicyVersion field and Global Vendor List (GVL) versions.
- ·v1 → v2.0 major changes (encoding format and API fully reworked)
- ·v2.0 → v2.1 (Purpose renaming / LI channel refinements)
Enter chapter→CMP registration & specification (TCF side)
partially integratedThe Consent Management Platform (CMP) registration process on the Transparency & Consent Framework (TCF) side, the semantics of the CmpId / CmpVersion fields, and the UI / API contract a CMP must implement. Division of labour with the cmp-api chapter: this one covers "who may become a CMP", cmp-api covers "how the browser reads it".
- ·The IAB Europe CMP registration process and CmpId allocation
- ·Field semantics of CmpId Int(12) / CmpVersion Int(12) / ConsentScreen Int(6)
Enter chapter→