Trademark authorities in Beijing have started looking into the iPad trademark case at the request of a Chinese company, which claims itself to be the rightful owner.

According to sources with the Beijing Administration for Industry and Commerce, an official investigation is being carried out by the administration's Xicheng District branch, which had received complaint from the Proview Technology (Shenzhen) in early 2011 claiming that Apple had been infringing on its iPad trademark.

Proview Technology (Shenzhen) is a subsidiary of the Hong Kong-headquartered Proview International Holdings Limited, which also has a branch in Taipei.

Proview Taipei registered the iPad trademark in a number of countries and regions as early as 2000, and Proview Shenzhen registered the trademark on the Chinese mainland in 2001.

Apple bought the rights to use the trademark from Proview Taipei in February 2010 via IP Application Development Limited, a company registered in Britain in. However, Proview Shenzhen claims it still reserves the right to use the trademark on the Chinese mainland. The two sides have been entangled in a legal battle ever since.

The Municipal Intermediate People's Court in Shenzhen rejected a lawsuit by Apple and IP accusing Proview Shenzhen of infringing on the iPad trademark in December 2011.

Apple has appealed to the Higher People's Court of Guangdong province. The case is still under trial.