The core specification's revision history runs 2.0.0 (October 2016, Bulletins 190 and 196), 2.1.0 (October 2017, Bulletins 204 v4 and 214 v1), 2.2.0 (December 2018, Bulletin 207), 2.3.0.0 (September 2021, Bulletin 227 v1), 2.3.1.0 (August 2022, Bulletin 256) and 2.3.1.1 (May 2023, Bulletin 294). Which protocol version numbers are active is set outside the core text, in Specification Bulletin 255, which also lists extension identifiers and SDK device information data versions. A message version not marked active there is refused with Error Code 102; the initiating component fixes the version and every component checks it stays the same through the transaction (Error Code 203 otherwise); components support every lower version still active and the latest patch of their own; the 3DS Server picks the highest version common to the ACS and DS lists cached from the PRes (and, in the app channel, the SDK). The SDK supports the newest device information data version and the ACS all active ones. Companion documents are the SDK, Split-SDK and SDK Device Information specifications, the SDK technical guide, the EMVCo message extensions, JSON message samples, app-based cryptographic worked samples and browser flow best practices. Normative references apply in their latest amended form unless dated. Products are approved by EMVCo: the Letters of Approval held (2024 to September 2026) approve 3DS Servers, ACSs, a DS and SDKs against core specification 2.3.1.1 and 2.2.0 with Bulletins 214 v3 and 255 v5 (SDKs also 309 v1), tested with the 2.3.1 and 2.2.0 test suites, valid for about two years and only while listed on EMVCo's site. EMVCo's page still showed 2.3.1.1 as current on 23 July 2026; Bulletins 279 (core) and 280 (SDK) were published on 11 August 2025.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.