haidynn: I told you, GoG doesn't grant you ownership either. Responding with more "But if GoG grants you ownership" style retorts isn't changing that Digital Products tend not to be ownable.
teceem: Define ownership.
Ownership gives you complete authority over something, which is why it's never actually possible to own another human being (said person has their own authority, so you can never gain complete authority.) You're not free to do whatever you want with the installer you download, nor are you free to do what ever you want with the files inside the installer.
The pitiful part is that the people who supposedly "own" the installer or "own" the gamefiles are completely helpless to stopping you from doing anything with it because they lack any authority over what happens to their code once it leaves their systems.
Then we get to legal ownership where someone says "I can prove I was the correct owner of this" but actually read the subscriber agreements... neither GoG nor Steam have any clauses saying that they are required to restore your access to your account or items on your account should you lose them for whatever reason. They may do so as a courtesy but they're not required to,
CDs are like Bearer bonds, the person who currently owns (meaning even if the CD was stolen from someone) the CD owns the license to play the game. You don't really get that with digital downloads, instead you get a license to use Steam to download and play the game with the steam client or a license to use GoG to just download the game. That you can't sell those licenses (unlike the CD) can also result in a dispute over who actually owns what.