Xperi Corp (formerly Tessera Holding Corporation) sued nVidia over their GPU for infringing on their five patents. Xperi is a patent troll. They’ve been trying to reach an agreement with nVidia over the past few years, but they have not been successful, so they sued.
In addition to audio and imaging codecs, the company has semiconductor packaging and interconnect licenses. They have also filed a lawsuit with Samsung and Broadcom, but have reached an agreement and signed a license agreement.
nVidia is a fabless semiconductor developer, the same as AMD and ARM etc. Its not at all clear how the litigation over patents will unfold as compared with Samsung who operates several foundries. Broadcom is less well known as a manufacturer of a range of devices. They are known for 802.11 products for mobile machines in addition to GSM hardware.