Four executives from a former online video service company pleaded not guilty to spreading pornography on the Internet when they stood trial in a Beijing court on Thursday.

The four worked for Shenzhen QVOD Technology Co in Guangdong province, including Wang Xin, the chief executive officer.

They are accused of using the video platform to make profits while knowing that a large amount of pornography had been uploaded, downloaded and watched, according to prosecutors.

The case, which was heard at Beijing Haidian District People's Court, drew an audience of about 100 to the court's public gallery, including media representatives and the defendants' family members.

Prosecutors said Beijing police selected 29,841 videos from three servers seized from the company for review, of which 21,251 included pornographic content.

The company, established in December 2007, advertised the provision of video services, but executives ignored whether information on the platform was legal or not and were involved in spreading pornography online, according to the prosecutors.

The company offered illegal videos through peer-to-peer video streaming technology, and the number of its users reached 300 million by September 2012, the prosecution said.

The four defendants denied the charge, saying they had reviewed content uploaded online and had never been reluctant to deal with illegal content.

Wang, the company CEO, said: "We could see and check the data uploaded or watched by our users but not the exact content. No one in the company would know whether the videos were pornographic.

"But we didn't give up on checking the uploaded information. We never ignored this," he said. "We cleaned our system to seek illegal content and also provided a channel for users to report any pornography they found."

Wang said the cleanup and the reporting systems, used since 2009, had played key roles in helping the company to find hundreds of illegal videos.

"We cleaned up these videos by filtering out key words provided by the Internet watchdog in Shenzhen, but we couldn't' rule out the possibility that some might get through," he said. "If a user changed a video document's name, it would be hard to find."