Bangalore: Apple has been sued by Chinese firm Zhizhen Network Technology Co. for a patent infringement pertaining to Siri. According to the shanghai based company, Apple has taken the applications of its product Xiao I Robot and used it in Siri; which is a voice activated feature for iPhone 4S, iPhone 5and iPad.

Apple has denied the claims at a hearing in Shanghai No.1 Intermediate People's Court, reports the Shanghai Daily newspaper. Apple said Zhizhen's accusation was unclear and lacked evidence, adding Siri did not violate the patent because it does not have a game server, which is one of the technical features of Xiao i. But the Shanghai company said there was infringement in the operation modes of Siri and Xiao i are the same.

"Apple has unveiled more products with the Siri application after we filed the lawsuit," said Yuan Yang, Zhizhen's lawyer. "We think all the above products infringed the patent right of Xiao i Robot voice recognition software."

A spokesperson from Zhizhen, said the company had been developing the Xiao i chat robot system since 2003. Zhizhen applied for patent rights for Xiao i in China in 2004 which came into effect in 2006. Siri, on the other hand, was developed in 2007 and Apple acquired Siri only in 2010.

According to an earlier report by Shanghai Daily newspaper, Zhizhen had filed a suit on June 21, 2012, requesting Apple to stop producing and selling products with Siri in China, but the hearing was delayed because the court decided to deliver the notice through diplomatic channels, as Apple is based in the United States.

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