Google has picked up a batch of 1,023 patents from IBM, adding to its portfolio of intellectual property it can use against rivals.
On Tuesday, the US Patent and Trademark Office published its record of the transaction, which happened on 17 August. In addition, IBM sold 1,000 patents to Google in May and turned over 30 more in June, making a total of at least 2,053 transfers from IBM to Google this year.
In August, Google accused rivals such as Apple, Microsoft and Oracle of ganging up on its Android operating system, saying these competitors are using "bogus patents" to wage a "hostile, organised campaign". The company's legal chief David Drummond said at the time that Google is being forced to beef up its own patent arsenal in order to fight back.
In addition, Google bid $900m (£553m) in April for a tranche of patents that became available with the bankruptcy of Nortel, though it lost out to a consortium that included Apple, Microsoft and Research In Motion.
"One of a company's best defences against [patent] litigation is... to have a formidable patent portfolio, as this helps maintain your freedom to develop new products and services," Google general counsel Kent Walker wrote in a blog at the time.
Since then, Google has handed over patents to HTC, which the Taiwanese Android device manufacturer immediately used to strike back against lawsuits from Apple. In addition, Google plans to buy Motorola's handset business, a deal that would bring it 17,000 patents and a further 7,000 patents pending.
The new batch of patents from IBM cover technologies such as "communications on a network", "secure password provision" and "dynamic manipulation of animated graphics in a web browser".
ZDNet UK has asked Google how much it paid for the IBM patents, but had received no reply at the time of writing.
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