This is usually how I would handle that communication:
BIM / CADD vector based electronic files and documents are an architect's professional instruments of service.
XXXX XXXX Architect is the copyright holder of these electronic CAD (.DWG) files and documents.
Any use of this electronic file information, in whole or in part, must be identified as, and include, the copyright of this architect.
Your work and copyright can be added as well for your firm's portion of the project scope.
We appreciate this collaboration and recognize the value of your contributions to the project.
Good luck
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William J. Martin AIA
WJM Architect
Westwood NJ
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