Apple Inc, the US electronics giant, appeared in court in Shanghai on Wednesday, accused of intellectual property right infringement involving software used on "Siri", its intelligent digital assistant.

Shanghai Zhizhen Network Technology Co, the developer of a voice technology called "Xiao i Robot", is alleging that the Apple assistant infringed its patent, in particular relating to "a type of instant messaging chat robot system".

Siri responds to a user's commands through voice recognition software.

A preliminary hearing - during which both sides can present evidence to the court before a formal hearing starts - was held at Shanghai No 1 Intermediate People's Court. The formal hearing is scheduled for July 2.

According to evidence presented by Zhizhen, its chat robot system was filed for patent with China's State Intellectual Property Office on Aug 13, 2004, and approved on Feb 15, 2006.

Siri Inc, a start-up company Apple acquired in 2010, started producing the virtual mobile assistant in 2007.

Apple included the technology on its iPhone 4S smart phone in 2011.

Apple, however, said Siri had gained an international patent and the company had applied to China's State Intellectual Property Office for the invalidation of Xiao i Robot's patent right.

Zhizhen Chairman Yuan Hui said his company demands Apple stop the infringement, and that means "Apple Computer Trading (Shanghai) Co and Apple Inc have to stop the manufacture, sale and use of products with Siri technology in China, such as iPhone 4S, iPhone 5, iPad 3, iPad 4 and iPod touch 5", explained Yuan Yang, an attorney representing Zhizhen.

"There are two possible results once the infringement is confirmed - Apple may bypass the Siri technology, or it may acquire or cooperate with Zhizhen in China," said Yuan.

Zhizhen filed the suit on June 21, 2012, only a few days after Apple paid $60 million to Proview Technology (Shenzhen) to end a protracted legal dispute over the iPad trademark in China.

The company said judging from the iPhone 4S' promotional slogan, which describes Siri as a character-driven intelligent personal assistant, Apple violated one of its patents.

"Xiao i Robot is not as famous as Siri only because we sell it as our technical core to varied types of clients, including China Merchants Bank and Shanghai Meteorological Bureau. Users get to know it under our clients' name," said Mei Li from Zhizhen's marketing department, adding that Xiao i Robot now has 100 million users across China, including some local government departments.

Apple said at Wednesday's hearing that detailed technical appraisal and analysis on Siri and Xiao i Robot should be presented as evidence to determine whether Siri has violated Zhizhen's intellectual property rights, which Zhizhen has failed to provide.

"The court only needs one essential technical feature to not rule the infringement, for example, unlike Xiao i Robot, Siri does not have a game platform," said Apple's attorney surnamed Yang.

This is the third time Apple has been sued in China for patent infringement.

It lost a battle for the use of the iPad name in China and was accused of infringing trademark rights by Jiangsu Xuebao Daily Chemical Co.

However, some industry insiders and lawyers doubt Zhizhen's motivation for filing the lawsuit.

Geng Yan, a smartphone specialist at CCID Consulting Co, said Siri and Xiao i Robot have overlapping functions such as online chatting and information inquiries, but that is common for technology companies.

"The settlement with Proview could be seen as a benchmark for what Apple is willing to pay for clean access to a trademark, but that would also embolden trademark trolls looking to make a quick buck off Apple," said Geng, adding there is also the possibility that Zhizhen is using the lawsuit to gauge its popularity on the domestic market.

Li Jinjian, a lawyer in Beijing who specializes in intellectual property, said that there is a reason why Zhizhen chose Apple rather than some small technology companies as its target to sue. "Because it's rich enough to pay," he said.

shiyingying@chinadaily.com.cn