I have been doing a lot of thinking about how software companies like Autodesk prove that someone has been using a pirated copy of their programs recently, because reasons. Other than the phone home and activation stuff in most of these programs, how do companies know? I'd assume other than hose two methods and reports, they'd have to rely on metadata in the files.
How can a regular user get a look at this metadata, beyond just opening the file in a text editor? Is there any sort of algorithm for encoding vertices in a specific pattern to identify the program that originates a file, or a way the software companies use to determine that from how a file is written or formatted or anything like that?
If you import a file into something like Blender or Open3mod, save it in the native format of said program, and then export from that program, does that remove any metadata or formatting clues that would identify the original program of origin?
Try adding a piece of irrelevant data into an OBJ or FBX file and you'll see it will corrupt the file and make it unreadable. Formats like FBX and OBJs are universal. They aren't created by Autodesk. They are very old and aren't designed to allow secret information to be hidden somewhere. If you open one you will see it only consists of vertex positions and UVmap coordinates. In the case of FBX it's a bit more complicated where it can also include rigs, vertex colors, bone weights, hierarchy groups and such. But even then any extended data added by Autodesk will be very apparent which can be spotted by any mediocre coder. If they hid something so subtle like the arrangement of vertex data, it will be incredibly vague for them to prove anything since it's not clearly branded.
Some software sends regular authentication checks to their database. But that only applies to registered licenses and is basically to confirm you've paid your (monthly) fee.
If you use some random pirated serial they don't know your company/location and is useless to them.
What happens mostly is that if you register a company a representative might come and check on how many computers you run their software compared to how many licenses you've bought.
do companies even do this? a lot of 3d file formats are pretty user readable, obj definitely has no metadata of any kind, can just be an ascii vert/normal/edge list
at the end of the day the company making the software is responsible for pursuing action against pirates and it's really not economically useful for them to go after small fry, it costs a lot of money to go after someone for piracy