The cardinalities on Claim presume that the only circumstances in which it will ever be exchanged is when actually requesting the processing of a Claim. It doesn't allow for the possibility of a Claim just being pointed to with some minimal identifying information. (In some cases you need more than just a bare identifier - because you might not have the identifier system due to the means of transport, so you need to convey additional information such as a date and/or patient identifier.) It's unreasonable to have to specify all the details of the Claim such as all of the coverages and their sequence, the Claim priority, etc. for this use-case.

As a general rule, resources should be designed with the presumption that they can be used for light-weight reference or summary purposes, not just for their submission purpose. It seems that the 'summary' elements were driven by the mandatories for submission rather than the mandatories being driven by what's reasonable to always require to be present in a summary.

(Please evaluate other FM resources for the same issue)