One of the biggest social game companies in the world is being investigated by regulators amid accusations of unfair business practices.
Japanese firm DeNA is facing accusations that it tried to stop developers publishing games on rival sites.
The group’s shares sank 10.5 per cent last night.
DeNA, which recently purchased casual games developer Ngmoco for $400 million, has confirmed it is being investigated by the Fair Trade Commission.
The firm operates a popular mobile-only social game site, called Mobage-town, which is said to have 20 million users in Japan.
One source told Reuters that regulators are looking into “whether DeNA had treated a mobile game developer unfairly after the developer created a game for a rival website owned by Gree Inc”.