SAN FRANCISCO - Google Inc. on Monday announced that it is bidding for patent portfolio of Nortel Networks in the bankruptcy auction for the Canadian telecommunications equipment maker.

In a press release, the Toronto-based Nortel said Google has agreed to buy all of its remaining patents and patent applications for US $900 million in cash.

Nortel, which filed for bankruptcy protection in 2009, expects the auction to be held in June this year, pending Canadian and US court approvals.

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Nortel has selected Google's bid as the "stalking-horse bid," or the starting point against which others will bid prior to the auction.

The agreement with Google includes the planned sale of about 6, 000 Nortel patents and patent applications spanning wireless, wireless 4G, data networking, optical, voice, Internet, service provider and semiconductors.

According to Nortel, the patent portfolio touches nearly every aspect of telecommunications and additional markets, including Internet search and social networking.

"This is an unprecedented opportunity to acquire one of the most extensive and compelling patent portfolios to ever come on the market," George Riedel, Nortel's chief strategy officer, said in a statement.

Google argued that the bid would help protect it from patent litigation and foster innovation.

The technology industry has recently seen an explosion in patent litigation, often involving low-quality software patents, which threatens to stifle innovation, Kent Walker, Google's general counsel, said in a blog post, believing the best defense against such litigation is to have a "formidable patent portfolio. "

"So after a lot of thought, we've decided to bid for Nortel's patent portfolio in the company's bankruptcy auction," he said.

"If successful, we hope this portfolio will not only create a disincentive for others to sue Google, but also help us, our partners and the open source community -- which is integrally involved in projects like Android and Chrome -- continue to innovate," Walker noted.