Mark Zuckerberg's Facebook is suing a South Korean firm it accuses of unlawfully using data to sell marketing and advertising.
Facebook is asking a judge to force the firm, 'Rankwave', to allow it to audit the firm’s activities to see if user data was obtained and potentially sold saying the move would "send a message to developers that Facebook is serious about enforcing our policies.
Facebook was investigating Rankwave’s data practices in relation to its advertising and marketing services," said Jessica Romero, Facebook's director of platform enforcement.
"Rankwave failed to co-operate with our efforts to verify their compliance with our policies, which we require of all developers using our platform."
According to court documents filed in California on Friday, Facebook is accusing Rankwave of using at least 30 different apps to "track and analyse" comments and likes on Facebook pages.
Rankwave also had a consumer app that, after gaining the user's consent, would track the popularity of that user's posts.The app would calculate a "social influence score", Facebook said.
However, the social network said it had information that since 2014, Rankwave had been using data gathered by its apps "for its own business purposes, which include providing consulting services to advertisers and marketing companies".