Patents can't be circumvented with the "Chinese wall" idea that happens with copyright-based reverse engineering. There is no alternative to licensing if you want to use a technology.
Oh it’s for copyright only. So what legal standing does Apple have and why didn’t they just pay the licensing fee? Unless they wanted litigation to go after these type of patents being sealed off?
Apple can attack the patent as being invalid (and go for an IPR), they can argue that they are not infringing, or they can pay a license fee. My guess is that Apple was too cheap to pay an acceptable license fee, so they figured they could strongarm this company in court.