DRM

But you don’t. For example, you cannot publish a derived work.

That's not how ownership/copyright of creative work is supposed to work. Even the guys at GNU will admit that and suggest to use some other kind of license if one really wants to not put limits on the use of their creation.

The question is about the ownership of the physical object, here the printed book not about the creative work it contains.

I own the book I purchase, it sits on a bookshelf in my home and, under no circumstances, can the seller or anyone enter my home to get that book back because they changed their mind or because they changed their agreement with the publisher and can't sell the book anymore. I purchased that book. I own it. It's mine, no matter what is their new situation. End of the story.

The same goes if say, a publisher was being forced to edit a book to change its content because some crowd or another find it offensive. They have no legal rights to enter my home to replace my non-edited older copy of the book with that new edited copy. That old version is my legal property even if they make a new one. That's what property and ownership is all about.

So, sure, I don't own the text in it I can"t change it and can't distribute my own copies of it but that has nothing with the ownership of the object I paid for, that is IP and copyright.

That being said, I still am allowed to do copies for my own personal use (it's written in the law, here in France that if I buy a book, a movie a CD I can make copies of it for my own usage, heck we even pay a 'copy tax' on every single empty storage support we buy to compensate for that). And I'm also allowed to do whatever derivative work I fancy from any existing work. Nobody can't say a thing, I'm just not allowed to distribute it. So, I could decide to write a follow-up to Anna Karenina telling how she comes back as an angry zombie I'm just not allowed to distribute it... Well, maybe Anna Karenina was not the best example since the text is in the public domain (I can sell derivative work if I fancy doing so) but you get the idea ;)