Facebook was fined $122 million for giving European Union antitrust regulators misleading or incorrect information about its acquisition of messaging service WhatsApp in 2014.
The fine is one of the largest that Facebook has received from an antitrust regulator, but officials said Thursday it also sends a warning message to other companies.
"Today's decision sends a clear signal to companies that they must comply with all aspects of EU merger rules, including the obligation to provide correct information," said Margrethe Vestager, the EU's Commissioner for Competition in a statement.
The Menlo Park tech firm told the European Commission, the executive arm of the EU, in 2014 that it couldn't automatically match Facebook's users' accounts to WhatsApp users' accounts.
But the commission found out that wasn't true and said that Facebook's staff knew about the possibility but failed to inform them.
Facebook purchased WhatsApp, which now has more than 1 billion users in over 180 countries, for $22 billion in 2014.
The commission said in a press release that Facebook was being fined for providing incorrect and misleading information in the merger notification form and in a reply to the commission's request for more information.
"The Commission considers that these infringements are serious because they prevented it from having all relevant information for the assessment of the transaction," according to the press release.
This isn't the first time that Facebook has landed in hot water with European antitrust regulators. The company has also faced privacy concerns over the data it collects from its users.
This week, French regulator, the Commission Nationale de l'Informatique et des Libertes, slapped Facebook with a $164,000 fine for running afoul of the country's data protection rules.