Google's chief legal officer David Drummond has hit out at Apple, Microsoft and Oracle for pursuing "bogus" patent claims, reports Corporate Counsel.

In an Google blog post entitled 'When patents attack Android', Drummond writes that the success of Android, Google's smartphone operating system, has prompted rivals Microsoft and Apple "to get into bed together" to purchase smartphone patents and has inspired a "hostile, organised campaign against Android by Microsoft, Oracle, Apple and other companies, waged through bogus patents."

Drummond's comments come after a consortium including Apple, Microsoft and Sony Ericsson last month outbid Google to purchase 6,000 strategic Nortel Networks patents for $4.5bn (£2.8bn), while late last year a group including Microsoft, Oracle and Apple acquired 882 patents from software company Novell.

Drummond (pictured) also alleges that Google's rivals have banded together to acquire large collections of patents in order "to make sure Google didn't get them," to make Android more expensive, and therefore "make it harder for manufacturers to sell Android devices." The strategy is "anti-competitive" and a "weapon" against innovation, Drummond writes.

In response to the blog, Microsoft's general counsel Brad Smith tweeted: "Google says we bought Novell patents to keep them from Google. Really? We asked them to bid jointly with us. They said no."

This was followed by a further tweet from Frank Shaw, head of corporate communications for Microsoft, linking to a corroborating email from Google general counsel Kent Walker to Brad Smith, declining to join Microsoft in the Novell bid. The email reads:

"After talking with people here, it sounds as though for various reasons a joint bid wouldn't be advisable for us on this one. But I appreciate your flagging it, and we're open to discussing other similar opportunities in the future."

Last month's competitive auction for the Nortel patents saw Herbert Smith take a lead role for Ernst & Young, the administrator to Nortel's EMEA entities, while US firm Cleary Gottlieb Steen & Hamilton acted for Nortel's US arm.

Corporate Counsel is a US affiliate title of Legal Week.