October 2010: Microsoft takes off the gloves and for selling Android-based phones that allegedly infringe upon Microsoft patents. Microsoft general counsel Horacio Gutierrez says that some of the patents in dispute related to Microsoft Exchange ActiveSync while others relate to on-screen displays for signal strength and battery power. Microsoft also buys dozens of smartphone patents formerly owned by Palm, further strengthening its smartphone patent portfolio.

November 2010: Vertical Computer Systems becomes the next company to file suit against vendors over alleged Android patent infringements, this time against Samsung and LG.

March 2011: Microsoft grows even more ambitious in its patent litigation by filing suit against Barnes & Noble over its use of Android as the operating system of its Nook e-reader.

June 2011: Two minor hardware players, Velocity Micro and General Dynamics, come to terms with Microsoft on a licensing agreement similar to the one Microsoft and HTC forged more than a year prior.

July 2011: Google's headaches continue to mount as the company to obtain valuable patents formerly held by Nortel to an industry consortium that included Apple and Microsoft. And Google doesn't just lose, it loses badly as its initial bid of $900 million for the patents is easily bested by the consortium's final winning bid of $4.5 billion. In all, Nortel sold more than 6,000 patents that covered technologies such as 4G , data networking and voice.