Copyright for 3D Scans
Sketchfab has published an article discussing copyright law as applied to 3D printing and scans. Public domain artworks and their replicas legally can be scanned and those scans shared based on a 1999 district court case involving photographic reproductions of public domain artworks. These scans and any models or prints made from the scans can be sold commercially because there is no copyright in the original works or in their replicas. The scans also do not qualify for copyright because they have been considered insufficiently original by the 10th Circuit.
However, any specific improvements or changes to the original scan or any creative additions to the scan, which are substantial and can be separated from the scan itself, may be copyrightable. The copyright would be limited to the modifications or additions. Any protection for the scan may be accomplished through contract.
More via Sketchfab.