So, if you bought a DVD licensed by Sony, can they now legally enter your house and take your DVD?
Or can Sony have some sort of DRM that prevents the DVD from playing when Sony loses the license agreement?
I’m just trying to reconcile how digital purchases can be subject to license terms changes, while a DVD apparently can’t be.
This isn’t entirely true and more so for Blu-ray disks. You own the physical media along with a temporary, limited license to watch the film on the media. That license is revocable and, technically, can be removed in the case of the publisher no longer being authorized to distribute licenses. It hasn’t really happened yet but Blu-ray players, as part of the spec, can connect to the internet to verify their licenses. If they wanted to, Sony could make your Blu-ray disks worthless if all your players follow the spec correctly. If you have a standalone drive or a drive hooked up to a computer that doesn’t fully follow the spec, you can copy the film from the media but you’d be breaking the law in most places for exactly the reason you’ve stated - breaking the encryption is illegal.
So there is a “license” with a DVD. It’s just far less enforceable than it is on a system where there’s no physical portion of the media for them to take away.
Another cool/scary feature of the BluRay spec is offline firmware updates (called BD+). Any disc can contain code that runs automatically and can patch the player firmware or execute arbitrary functions. So if you have an older hacked player and you insert a newer disc into it, the AACS Consortium has the ability to brick it. Or if you “own” an older disc but the Consortium starts to dislike it for some reason (maybe they discovered that the disc was printed by a pirate publisher, or maybe there was a retroactive licensing dispute), they can include code on every newly published disc that blacklists the old disc. Even with a standalone player that you never connect to the internet, the moment you insert any new disc into it, your old “problematic” disc will be unplayable. This has never yet happened with a previously-legal disc AFAIK, but it is possible within the spec. Every player manufacturer must obey the spec and implement the BD+ virtual machine in order to be allowed to read AACS content. And if you hack your player to ignore BD+ code, then the newer disc will not play because its content may be scrambled in a way that only the custom BD+ code included with it can unscramble.
Yup. That’s why you buy non-spec drives and backup your own shit.
That’s true, blu rays came with updatable firmware that you had to keep nice and happy or they’d stop playing. Like one other commenter said - you own the disc, and the bytes on them. If it’s playable is a whole other story