Android-owner Google has accused rival firms, including Microsoft and Apple, of pursuing bogus patent claims in a bid to kill its popular operating system.

David Drummond, chief legal officer at Google, said grand success of Android operating system had forced its rivals to unite and wage an organized hostile campaign against Android.

In the blog post, entitled “When patents attack Android”, Drummond wrote, "Patents were meant to encourage innovation, but lately they are being used as a weapon to stop it."

He added that bogus patents were being used to drive up the costs of Android-based devices.

Mr. Drummond’s comments emerged after Google lost several patent battles. In recent months, Google lost auctions for a huge number of patents held by Novell and Nortel. A group of tech giants, including Microsoft and Apple, finally purchased those patents. Many of those patents relate to technologies which can be used in smartphones.

In response, Microsoft claimed that they asked Google to bid jointly with them for the patents, but it refused.