Google's chief legal officer has issued a blistering attack on rivals seeking to entangle Android and the manufacturers that use the software in costly legal cases.
David Drummond claimed that Google is under a hostile attack organised by Microsoft, Oracle, Apple and others based on patent law and pricing.
This involved the $4.5bn purchase of Nortel's patents, well above the $1bn guide price, and taking legal action against companies that use Android, such as HTC, Motorola and Samsung.
"We're not naive; technology is a tough and ever-changing industry and we work very hard to stay focused on our own business and make better products," he wrote on the Google blog.
"But in this instance we thought it was important to speak out and make it clear that we're determined to preserve Android as a competitive choice for consumers by stopping those who are trying to strangle it."
A modern smartphone could contain the ingredients for 250,000 patent claims, he said, and the cost of litigating on all of them would be high. In addition, actions like seeking a surcharge for Android handsets are designed to make them more expensive than those using Microsoft's Windows Phone 7.
Drummond explained that he is encouraged by the investigation by the US Department of Justice into the Nortel patents purchase to determine whether it was carried out for anti-competitive purposes.
Google will strengthen its own patent portfolio in the future, he said.
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