TOKYO – A sushi restaurant chain is suing a customer for 67 million yen (S$645,000), saying a viral online video of the teen licking communal bottles and plates caused a drop in sales, foot traffic and the company’s shares, according to Japanese media.

Food & Life which owns Akindo Sushiro, the outlet where the incident occurred, filed a police report and received an apology from the perpetrator. In the clip, he also touched the sushi as it rolled past with fingers he had put in his mouth.

Sushiro is Japan’s largest conveyor-belt sushi chain.

Losses amounted to 16 billion yen when shares of the parent company fell 4.8 per cent on Jan 31, according to national broadcaster NHK and the Yomiuri newspaper.

The phenomenon, dubbed “sushi terrorism”, sparked a wave of copycat incidents shortly after the video, taken in Gifu city, quickly spread across social media platforms, including Twitter.

A spokesman for the sushi company declined to comment on an individual case. A spokesman for the Osaka District Court said it could not provide details but confirmed the litigation.

The chain added acrylic screens at some outlets to deter tampering on its conveyor belts, and said it would provide fresh seasonings and cutlery to those who request it, the costs for which it is seeking recompense from the teen.

Two other major conveyor-belt sushi chains, Zensho Holdings-owned Hamasushi and Kura Sushi, told Bloomberg News in February that they were considering methods such as deploying artificial intelligence and cameras to thwart potential pranksters. BLOOMBERG