Facebook is facing more than just user backlash following news that the social network was purposely trying to manipulate user emotions during a 2012 experiment.

The Information Commissioner’s Office (ICO), a data regulator in the United Kingdom, is investigating whether or not Facebook violated data collection laws during a user study more than two years ago, according to the Financial Times.

During the study, the social network tweaked the News Feed content of nearly 700,000 users, providing some users with fewer negative terms, and others with fewer positive terms. Users were not alerted that they were being used as test subjects, and the study raised privacy concerns when the data was published.

At this point, the ICO is unsure whether or not Facebook actually broke any laws. But, because Facebook’s European headquarters are based in Dublin, the agency plans to contact Ireland’s data protection group about the matter, according to the Financial Times. The IOC can “force organizations to change their policies and levy fines of up to 500,000 British pounds [about $857,000],” the FT wrote.

Financially, that type of monetary punishment (it’s less than $1 million) won’t hurt Facebook, which brought in $2.5 billion in revenue last quarter. Instead, any type of monetary fine would be symbolic.

“It’s clear that people were upset by this study and we take responsibility for it. We want to do better in the future and are improving our process based on this feedback,” a Facebook spokesperson wrote in a statement given to Mashable. “The study was done with appropriate protections for people’s information and we are happy to answer any questions regulators may have.”

Privacy experts in the U.S. told Mashable that Facebook probably didn’t break any laws.

Initial reports claimed that Facebook’s Data Use Policy included “data analysis, testing, [and] research” as possible ways Facebook could utilize user data. However, a Forbes report, which surfaced Monday, found that Facebook added this line about testing and research four months after the emotion-manipulation study actually took place.

Facebook tweaks its News Feed often to surface different types of content for users in hopes of generating more engagement (Likes, shares, clicks, etc.). Nevertheless, the implications surrounding this type of study appear to be more troubling than usual for those users who don’t appreciate Facebook experimenting on them.

Facebook already struggles with user trust issues when it comes to privacy, and this experiment isn’t helping the company’s cause.

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