Britain’s Information Commissioner’s Office said it would look into the Facebook experiment. That’s one problem for Facebook. Another is a potential class-action suit:

Critics of Facebook’s study have raised the specter that the company could face a class-action lawsuit over the study. According to a report in Forbes, the company added mention of research to its terms of service months after the study was conducted.

Julia Horwitz, a consumer protections counsel at the Electronic Privacy Information Center, said however that other portions of the user agreement could protect Facebook from legal action.

Horwitz, however, said she believes the study may have violated Facebook’s agreement with the FTC, which called for better transparency in how user information was being used.

Troubles for the little f.