Photo/Illutration Akindo Sushiro Co. operates more than 600 Sushiro outlets across Japan. (Tomohiko Kaneko)

OSAKA--A teacup-licking, saliva-spreading diner has asked a court to dismiss a lawsuit filed against him by a sushi chain operator that is seeking 67 million yen ($480,000) in damages for the unhygienic prank.

Details of the lawsuit were recently revealed.

The defendant, who lives in Gifu Prefecture, expressed regret on May 11 for what he had done at the chain’s outlet in Gifu in January. He said he and his friend who recorded the prank did not intend for the footage to be shared with a third party and go viral on social media.

But he disputed the argument of Akindo Sushiro Co., the operator of the conveyor-belt sushi chain, that the prank led to a sharp decline in revenue across Japan. He said competition with other chains may have caused the company’s sales to drop.

According to the lawsuit filed at the Osaka District Court in March, the man filmed himself licking the rims of teacups and the open top of a soy sauce bottle in January at the Gifu outlet.

He is also seen in the video putting his saliva on a dish of sushi before it was served to another customer.

The sushi chain said sales plunged at its outlets across the country and its share price nose-dived after the video circulated online.

The operator also said it had to spend millions of yen to take steps to prevent a recurrence.