The second edition of AP238 is currently under development. The primary goals are to track the new features added to the STEP CAD track by AP242 and to integrate lessons learned from testing and production experience. A working draft of the new document is available on github.
During testing and develoment, WG15 is using an EXPRESS model that combines the latest definitions from AP242, AP238, and extensions identified during testing.
The following is a general overview of the second edition activity
Finally, the documents below give specific changes for the
second edition that were identified during testing. The first
document is a detailed spec, but the second one is an overview
presentation that is a bit more readable. Dave Loffredo was
the editor of the first edition and can be reached with
specific questions at