The case against the Chinese government body, which is in charge of patent rights protection in the country, and Zhizhen Network Technology, a Shanghai-based firm that owns a voice recognition software called "Xiao i", was heard in a Beijing Intermediate People's Court last Thursday.

The hearing lasted over five hours and the court didn't make any decision immediately, according to a Sina news report.

In June 2012, the Shanghai firm accused Apple's Siri of infringing its patent "Xiao i" which was developed as a chatbot for popular messaging networks including MSN and Yahoo Messenger. It was granted patent rights in China in 2004, ahead of Siri that was widely used in Apple’s later products, Zhizhen claimed. Apple acquired Siri in 2010, and debuted the feature in launch of its popular iPhone 4S in 2011.

On November 19, 2012, Apple requested the Patent Reexamination Board of SIPO to invalid the patent of Zhizhen’s "Xiao i" as it lacked "novelty and creativity". The Chinese patent also failed to carry out a detailed description of its specification and it cannot achieve some specific functions, Apple declared. The request was denied by the board subsequently on September 16, 2013, prompting Apple's legal action.

During the trial on Thursday, Apple's attorney requested an overturn of the decision from Patent Reexamination Board of SIPO in September last year, as it was crucial to the ongoing patent dispute between Apple and Zhizhen since 2012, according to the Sina report.

The evidence and defense opinion presented by Apple this time was not much different from the past, and the outcome is unlikely to see a difference, a co-founder of "Xiao i" said the same day, added the report.