FSF has opinions but not case law - anyone else's opinion is as valid, there's no citation because no court has ruled that dynamic linking is or isn't a derivative work.

You have to construct your own view based on existing statute and vaguely related cases.

Google LLC v. Oracle America, Inc., 593 U.S. 1 (2021) is not a pro-FSF opinion.

Whether linking (dynamic or not) is a derivative work is defined by things like incorporation, similarity, and creative expression.

I think the FSF view is unreasonably confident in its public opinions where the current law is that each potential infraction is going to be decided on a case by case basis. Read 17 USC 101 for yourself and square that with FSF/Stallman opinions.

There's too much nuance to have a stance about what happens when you link a program. "It depends" is the only thing you can say.

I would point towards Oracle v. Rimini, where the Ninth Circuit has specifically ruled (inside a complex and yet-unresolved case) that a system built to interoperate with a copyrighted program does not constitute a derivative work of that program. (https://cdn.ca9.uscourts.gov/datastore/opinions/2024/12/16/2...)

They reference a less on point but better known case (https://en.wikipedia.org/wiki/Lewis_Galoob_Toys,_Inc._v._Nin...., for some reason you have to manually add the period at the end of the link) about whether NES cheat cartridges were copyright infringement. If a work that directly links to and interoperates with a program is a derivative work of that program, the Game Genie really was illegal after all. To me that doesn't seem right, and given the FSF's general opinion on console restrictions (https://www.fsf.org/bulletin/2025/winter/new-nintendo-drm-ba...) I kinda feel like they'd have to agree.