If so a blockchain of its own is needless "bloat"; one could simply offer customers a range of costs of existing, expected to be secure chains on which to record a cryptographic proof, no need to store entire object, owner of object can retain actual object / 3D-file as long as they feel they need, holding also along with it algorithm / program that creates the algorithmic proof given the actual file.

Some customers might choose to have their proof written to bitcoin blockchain, others maybe even also to various other chains as redundancy.

-MarkM-