A condom maker in South China's Guangdong province has won a lawsuit against a Japanese company over its competing claim to be manufacturer of the world's thinnest prophylactic.

The Guangzhou Yuexiu District People's Court pronounced on Monday that Tokyo-based condom brand Okamoto used unfair practices to compete against Guangzhou Daming United Rubber Products.

Guinness World Records verified the Chinese company's Aoni condom, which has an average thickness of 0.036 mm, as the world's thinnest in December 2013 - breaking the previous record of 0.038 mm set by Okamoto in 2012.