LOS ANGELES - Google Inc, fresh off losing a bid to buy thousands of valuable patents from bankrupt Nortel, accused its biggest rivals on Wednesday of banding together to block the Internet giant in the red-hot smartphone arena.

"Microsoft and Apple have always been at each other's throats, so when they get into bed together you have to start wondering what's going on," Drummond wrote in a blog post. He referred to "a hostile, organized campaign against Android by Microsoft, Oracle, Apple and other companies, waged through bogus patents."

An Apple spokesman declined to comment.

In a rare public outburst, Google Chief Legal Officer David Drummond blasted Microsoft, Apple, Oracle and "other companies" for colluding to hamper the increasingly popular Android mobile software by buying up patents, effectively imposing a "tax" on Android cellphones. Apart from increasing costs for consumers, snapping up the patents will stifle technological innovation, he said.

 

Google is forging ahead in the smartphone market but has been hampered by a lack of intellectual property in wireless telephony, which has exposed it to patent-infringement lawsuits from rivals including Oracle.

It lost out on the Nortel patents to a consortium grouping Apple, Microsoft, Research in Motion and others, which together paid $4.5 billion.

Google individually had bid up to $3.4 billion for those patents before teaming up with Intel Corp, which on its own had bid up to $3.1 billion, according to a source familiar with the matter. They bid through $4 billion and then tapped out, another source had told Reuters.

The Internet search leader is now in talks to buy InterDigital, a key holder of wireless patents valued at more than $3 billion, according to the Wall Street Journal.

Google, being a software company, was not focused on patents for a long time but is now shopping to stock up. It recently acquired over 1,000 patents from IBM.