[sans_seraph]

Sim locking is purposely breaking the normal functionality of a device in order to limit competition.

I wouldn't care so much if there were plenty of other affordable ways to get a phone and coverage, but sim locking is so prevalent in the US that it's unavoidable in many cases, and most phones you can get unlocked are incredibly expensive.

[eropple]

OK, thanks. Now please explain how any of these companies fall under antitrust definitions.

(I'll save you the effort: they don't. None have sufficient market share that anyone would go after them and there are enough BYO provides to look at that there's no way you'll win a claim you don't have choice.)