The third edition of AP238 was published in 2022 and is available for purchase from the ISO website as ISO 10303-238:2022(E). This is the current version.
This is a minor revision that maintains harmonization with AP242 third edition through shared use of the ISO 10303 resource parts collectively published as version 9 of the STEP module and resource library.
Together with the second edition, AP238 now incorporates experience accumulated from deployment of the first edition since 2007, full integration with AP242, the latest semantic tolerances and geometric representations, initial support for additive manufacturing process, and capture of digital twins resulting from manufacturing.
STEP APs have a very formal structure with resource and implementation schemas. The latest long-form EXPRESS model for AP238e3 can be found in Annex I. The following diagrams for the latest ARM and AIM are the definitions that WG15 uses in testing and development.