Isn't it the same thing?
Stuff you fully control is stuff you own fully.
Stuff you don't fully control is stuff you don't own fully.
Stuff you fully own is stuff you fully control.
Stuff you don't fully own is stuff you don't fully control.
As I mentioned, "ownership" is not always such an absolute concept outside the USA, which began as a freewheeling frontier society. For example, the French translation of "company" is "société", and the thing is understood to be a bundle of obligations rather than a discrete object to be bought and sold. Even in England, houses are commonly sold on leases rather than the "freehold" which is intrinsic to ownership in the US.
IMO the verb "own" is only fully unambiguous in the case of non-fungible physical goods. Which clearly data is not.
So by your logic, if I steal something, I own it?
I've been asked to own several microservices, yet I'm not allowed to share their code with people, am I therefore barred from actually owning them?
If I have my DNA sequenced, there's a possibility that the company that did the work made a copy. Do I not own that data because of the mere possibility that they could share it with somebody in the future without my consent? Is the only way to retain ownership of that data to do the sequencing myself?
If I record a song, somebody copies it, and then something destroys the original, does the copier now own it instead of me?
It all seems very inconsistent to me. Better to just drop the word all together when it comes to data and handle each case independently.