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Each metadata template represents a change in the RTS, where a change is typically something that happens to a template. We currently recognize three major changes that happen to in an RTS: insertion of a template : insertion into the RTS (essentially creation), invalidation of an existing template, and re-validation of a template (that was previously invalidated). We describe these changes below. Also, assignment of an instance unique identifier (IUI) is something that happens in the RTS. Currently, these changes are captured in A templates. At this time, we do not propose to change how IUI assignments are captured as A templates.
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