Richard,
I'm glad that you are posting this information to the PMKC community, as it will likely generate many good responses. Regardless of the advice you get from this forum, please make sure that you get advice from a Pennsylvania attorney fluent with architectural practice, licensing regulations and copyright protection, and from your insurance company. You might also want to get input from your State licensing board.
If I'm interpreting your question correctly that your client is asking you to develop drawings and the client will then retain another architect as the architect-of-record, than your exposure can probably be addressed by a tight contract between you and your client that indemnifies and holds your harmless. The architect-of-record will have the bulk of the exposure. You might also consider asking your attorney whether you should insist on language in your client-architect contract obligating your client to incorporate indemnification and hold harmless clauses of you by the architect-of-record.
Good luck with this. It's tricky business.
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Michael Strogoff, FAIA
Strogoff Consulting
Mill Valley CA
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