According to an article on 9to5Mac, Apple’s new iPhone 4S antenna design may infringe Samsung patents. From the article:

Pedersen and others at the Aalborg University think Apple will run into legal issues related to patents the professors sold to Samsung in 2007. The report also notes Samsung has not yet used these patents in litigation with Apple.

Regarding implementing a multi-antenna design that intelligently switches to improve reception, Danish professor Gert Frølund Pedersen stated:

“I can not say that they are directly breaking the patent, but there are not many ways they can choose the right antenna, without coming to break many patents.”