Disputes over online trademark infringement are rising sharply as e-commerce flourishes, a spokesman for the Supreme People's Court said on Tuesday.

Nearly 13,000 trademark disputes were received by courts across the country in the past year, an annual rise of 54 percent, statistics from the court showed.

"A considerable number of these cases were triggered on the Internet, although we didn't make a specific count," said Sun Jungong, spokesman of the top court. "And the proportion is increasing."

A trademark carries the reputation of a business and plays a big role in market competition, according to Sun.

"Unfortunately, well-known trademarks, which provide an edge for their companies, are also more prone to piracy."

Moreover, when administering justice in similar cases, courts at various levels gave completely different verdicts, especially when it comes to the responsibility of the online service providers.

In a case last year, clothing trader Eland Shanghai found that online clothing shop owner Du Guofa used the company's trademark and logos on the clothes sold in his shop on taobao.com, a leading Chinese online marketplace. The company sued Du and the website.

The court ruled that the website bore liability for the infringement because it did not take effective and necessary measures to stop and prevent the suit.

However, in another case, popular paint brand Nippon Paint found Shanghai Zhanjin Trading using trademarks and print advertisements unauthorized by Nippon on its taobao.com store in March 2011. Shanghai's Xuhui District Court concluded the practice was consistent with commercial practice, and the case was not deemed an infringement.

"The court's decision showed that its understanding of the function and values of trademark is one-sided and obsolete," said Wu Jialun, director of public relations and brand communication of Nippon Paint China, adding that the company has appealed to the intermediate court, and the hearing will be held on April 25.

"As an online shopping website, Taobao should verify and oversee the businesses on the platform," she said. "And it should perform timely and effective remedial obligations after knowing some merchants commit acts of infringement."

Zuo Chen, a spokesman with Alibaba Group, parent company of Taobao, said it has specialized channels for complaints of trademark infringements on its website.

"And we will force sellers to remove the logos if they fail to provide certificates of trademark registration after being reported," said Zuo. "There's no more we can do as an Internet service provider."

Online marketplaces can take other steps, said lawyers, such as asking retailers to submit evidence of trademark ownership when registering on the platforms as well as expelling lawbreakers.

Lawyers said it is understandable that courts give different decisions when handling similar cases since e-commerce disputes are new.

"So it is significant that the top court has issued 10 representative cases of intellectual property rights, which can act as valuable references for judges and ensure the consistency of law enforcement," said Yi Shenghua, a Beijing-based lawyer from Yingke Law Firm.