Google\'s top lawyer accused Apple, Oracle, Microsoft and other companies of using \"bogus patents\" to wage a campaign against the Internet giant\'s Android mobile platform. In a blog post, Google senior vice president and chief legal officer David Drummond said Google\'s rivals were seeking to \"make it harder for manufacturers to sell Android devices.\" \"Instead of competing by building new features or devices, they are fighting through litigation,\" Drummond said. He said 550,000 Android devices were being activated every day and its success has resulted in a \"hostile, organized campaign against Android by Microsoft, Oracle, Apple and other companies, waged through bogus patents.\" Drummond pointed to last year\'s $450 million acquisition of 882 patents from software maker Novell by a consortium made up Microsoft, Apple, EMC and Oracle and the more recent purchase by a group led by Apple and Microsoft of 6,000 patents held by bankrupt Canadian firm Nortel. Google was a bidder for the Nortel patent portfolio but it lost out to a $4.5 billion bid from the consortium made up of iPhone maker Apple, EMC, Ericsson, Microsoft, Blackberry maker Research in Motion and Japan\'s Sony. The huge sum spent on the patents and the involvement of many of the world\'s top tech companies reflected the fierce battle for intellectual property in the tech industry, where firms are often hit with patent-infringement lawsuits. Google is currently being sued by software giant Oracle over technology used in its Android smartphone operating system. Drummond said Google\'s rivals were \"banding together\" and were seeking a $15 licensing fee for every Android device. He said they were also \"attempting to make it more expensive for phone manufacturers to license Android,\" which Google provides for free to handset makers. \"Patents were meant to encourage innovation, but lately they are being used as a weapon to stop it,\" Drummond said. \"A smartphone might involve as many as 250,000 (largely questionable) patent claims, and our competitors want to impose a \'tax\' for these dubious patents that makes Android devices more expensive for consumers. \"Fortunately, the law frowns on the accumulation of dubious patents for anti-competitive means -- which means these deals are likely to draw regulatory scrutiny, and this patent bubble will pop,\" he continued. Drummond said Google was encouraged that the US Justice Department is looking into whether Microsoft and Apple acquired the Nortel patents for \"anti-competitive means.\" \"We\'re also looking at other ways to reduce the anti-competitive threats against Android by strengthening our own patent portfolio,\" he said. \"We\'re determined to preserve Android as a competitive choice for consumers, by stopping those who are trying to strangle it.\" Microsoft general counsel Brad Smith responded to the Google accusations with a message on his Twitter feed. \"Google says we bought Novell patents to keep them from Google. Really? We asked them to bid jointly with us. They said no,\" Smith said. Apple or Oracle did not immediately respond to requests for comment.