So the law which they're using here says that only the copyright owner is allowed to modify or rearrange (whatever that means) a program. Couldn't you argue that an adblocker doesn't do that? I run the "program" of the web site host, which produces a DOM tree in the browser. Then I run a second program, the adblocker, which removes certain elements from the DOM tree before rendering. At no point am I modifying their code. At most, I'm modifying the browser's program, but since the browser has an interface to facilitate precisely that in the form of addons, we can safely assume that the manufacturer of the browser is fine with that.

Edit: nevermind, I read the whole thing. The lower court argued as I did, but in revision they apparently found that the DOM tree is code generated by code and thus an expression of the program.

> but in revision they apparently found that the DOM tree is code generated by code and thus an expression of the program.

It would seem to me because user browsers are user-modifiable open source, there really shouldn't be any deep expectation by any web content producer that the generated code into DOM will be displayed in any user consistent manner. But I suppose if that was accepted rational, that means ad blockers should sit deeper in the browser (or at the network level) to avoid problems with countries that view personal modification as digital copyright infringement if the license doesn't allow it. That should secure ad blocking — until legislation specifically bans ad blockers as a function completely...

It feels like it would be a big step to move from gatekeeping personal modification, to compelling code generation by the user from the framework of copyright.