It can reasonably be assumed that corpses on dedicated locations like cemetery should be protected while there are direct live connections (kids, partners). Let

It can reasonably be assumed that corpses on dedicated locations like cemetery should be protected while there are direct live connections (kids, partners). Lets say 100 years at most although it is probably overkill. However, even today if you don't pay a parcel rent, cemetery can dig the corpse up and ditch it. Entire first generation of cryogenic people were lost due to this problem (grandkid didn't want to pay for grandpa for eternity in cryogenic coffin). So with all this in mind, it makes sense that after your are legally dead and lets say 1 year passed (to allow for the "return from the dead" cases we know happen), you should be considered dead nature. After that time, it becomes a matter of your relationship with the cemetery or other company and contract you have with them. If their "SLA" is that they will "own" it for you, then digging it up can be considered legally as a theft. If you have culture that wants to keep dead forever, then that culture will find ways to manage it the official way I guess along with the laws on theft, and wont leave it to the little dwarfs to manage. You must keep in mind tho that each day number of dead people is rising and number of alive stays close to the same. Any civilization wanting to keep dead forever will have a lot of problems with this idea, unless it can find a way to teleport them to different dead dimension unrelated to us. Such advanced civilization will sure have much better way to preserve uniqness of each individual.