Apple Inc's recent iPad trademark dispute has caused concerns among international companies over the legitimacy of their own trademarks in the Chinese market. Social media giant Facebook has reportedly started registering relevant trademarks in China, yet found that some of them have been taken.

According to information on the website of the Trademark Office of China's industry and commerce authority, Facebook started trademark registration in China back in 2006 and has filed 61 applications on the "Facebook" name, both in English and Chinese.

However, some of these names, such as the Chinese translation of "Facebook", have already been registered by domestic users, said Facebook's representative East IP Group.

"We are collecting evidence, hoping to reclaim these trademarks based on Facebook's popularity and social awareness," said an employee at East IP.

China's business press carried the story above on Friday.

Contact the writer of this story at: yanp@china.org.cn.