My firm does mostly public work (schools, libraries, fed, state and local govt). In the case where we do work with Montgomery County (MD) Public Schools, technically they own the rights to the CAD drawings since they are the owner and are paying us. However, if a contractor or subcontractor requests CAD files, we make them sign an agreement and pay us per the number of drawings they want. The agreement states they will not just use the files for shop drawings, but that they must create their own drawings.
I have also done some work on behalf of a tenant and teh landlord was able to provide me a CAD drawing. However, I would check the lease first. I believe whoever your client is/was technically owns the CAD files as well.
Hope this might help.
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Robert Emard AIA, NCARB, LEED AP BD+C
Project Architect
The Lukmire Partnership, Inc.
Arlington VA
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