Any way to copyright a model?

Is there a good way to copyright a model file (sldprt or sldasm)?  Our drawings clearly identify copyright, export info, etc, but our models have no such distinction.  We're getting ready to transfer a large amount of IP to a partner, and I think it would be good to identify these model files in the event that there was a question later on whether someone was using files that we created. 

Thanks,

Kevin

SolidworksGeneral