In a patent dispute that started in 2010, over a patent dating back to 1994, Nokia and Sony (under the flag of MobileMedia Ideas LLC) have won a court battle with Apple over infringement of the patent by a number of Apple's iPhones.
The US patent relates to a method for silencing the ring tone for incoming calls before the call is answered, e.g. by pressing a particular key on the phone. Sony originally filed the patent in 1994 but later assigned the patent to MobileMedia (a non-practicing, patent licensing entity).
Back in 2010, MobileMedia (in which both Nokia and Sony have an ownership stake) sued Apple in the US for infringement of 16 of its patents. However, over the course of the litigation this was whittled down to the single ring tone patent. After a number of court hearings and appeals, a Federal court in Delaware found Apple to have infringed MobileMedia's patent.
The court have awarded MobileMedia $3m in damages from Apple, which is mere loose change compared to the $18m MobileMedia had petitioned for.
In 1994, Sony patented a method for users to control incoming calls on a mobile phone, whereby an alert sound would be either stopped, or the sound would reduce after the initial loud alert, provided the user was able to signal that they were aware of the call.