Expansion parameters determine how vocabulary expansions work.  They may have a bearing on how systems are expected to conform.  For example, if a specification has expansion parameters that limit it to a specific release or version of SNOMED or some other code system, the intention may be that implementers are limited to that release or version.  However, at present, we don't surface those terminology constraints in a visible way to readers, nor do we make clear whether those constraints are for publishing convenience, or rules for conformance.  Perhaps we need distinct expansion parameters for each?  In any event, we definitely need to make this information visible to others so implementers are clear on what rules they must follow for their terminologies.  They will potentially also want access to the parameters so they can use when testing.

Finally, we're not currently examining the differences between expansion parameters between an IG and the expansion parameters of the IGs it depends on.  What happens when these are inconsistent?