The probe follows a weekend of turmoil for the social media giant. Reports this weekend said the research firm improperly gained access to the data of more than 50 million Facebook users.
"We are aware of the issues that have been raised but cannot comment on whether we are investigating. We take any allegations of violations of our consent decrees very seriously as we did in 2012 in a privacy case involving Google," a spokesman for the FTC said Tuesday.
Facebook said Tuesday it expected to receive a letter from the FTC with questions, but has not been informed of a formal probe.
A violation of the consent decree could carry a penalty of $40,000 per violation, which could mean a fine conservatively estimated to be "many millions of dollars in fines" for Facebook, The Washington Post reported over the weekend, citing a former FTC official.