Google has acquired more IBM patents, adding more than 200 to approximately 2,000 patents it had previously bought from IBM.
 
 The move, first reported by the blog SEO by the Sea, was confirmed by a Google spokesman who  didn't immediately comment on why the company is interested in these  particular patents and on how they may benefit Google products and its  customers.
 
 The latest set of IBM patents, transferred to Google on Dec. 30, 2011, includes 222 patents and covers a variety of technologies, including email management,  server backup, tuning and recovery, e-commerce, advertising, mobile Web  page display, instant messaging, online calendaring and database tuning.  Google acquired about 1,000 IBM patents in July of last year and about  1,000 other IBM patents in September.
 
 In the past, Google officials have said that acquiring patents helps the  company prevent intellectual-property lawsuits and that, when one is  filed against it, patents boost Google's ability to defend itself.
 
 It's hard to determine which patents represent technology that Google  plans to develop and which ones are intended as litigation protection,  said IDC analyst William Stofega.
 
 However, considering the rash of IP-related lawsuits in the mobile  market, it's safe to assume that many mobile-related patents Google  acquires are meant to strengthen its ability to fight lawsuits, said  Stofega, who is IDC's program director of mobile device technology and  trends.
 
 "Google has had a great run with what they've done so far and it's clear  their patent portfolio isn't as rich as those of others, especially in  mobile," he said. "If you're going to be a mobile platform player, you  need to make sure you have your ducks in a row regarding intellectual  property."
 
 A large part of Google's motivation for buying Motorola Mobility is the  latter's patent portfolio, which includes more than 24,000 patents. That  $12.5 billion deal is due to close early this year, after the companies  obtain all necessary approvals.
