SAN FRANCISCO — The Federal Trade Commission is considering seeking a preliminary injunction against Facebook to prevent the social network from integrating several of its messaging services, according to three people with knowledge of the matter.
The agency has discussed how the Silicon Valley company is stitching together the technical infrastructure underlying WhatsApp, Instagram and Facebook Messenger, said the people, who spoke on the condition of anonymity because the talks are confidential.
The F.T.C. is weighing whether such an integration would make it harder to potentially break up Facebook, they said, especially if the agency determines that the company’s acquisitions of some of those apps reduced competition in social networking. The agency has not made a final decision about what to do, the people said.
The F.T.C. and Facebook declined to comment. The potential injunction was reported earlier by The Wall Street Journal.
Seeking an injunction of this kind would be an uncommon step for a federal antitrust agency because officials rarely consider unwinding mergers that have already closed. A majority of F.T.C. commissioners would need to approve the move in a formal vote, said an agency official who was not authorized to speak publicly.
The agency would face a high bar in court to show that Facebook was about to violate antitrust laws or already had, this person said. A court is unlikely to issue an injunction simply to give the commission more time to investigate, the person said.
For months, Mark Zuckerberg, Facebook’s chief executive, has been working to unify the technical systems of WhatsApp, Instagram and Facebook Messenger. That would allow Facebook’s more than 2.7 billion users to communicate across the platforms, so messages sent through WhatsApp could be received by users who have Facebook accounts and forwarded, in turn, to people on Instagram.
In March, Mr. Zuckerberg said he was trying to unify the apps so that people could engage more easily in private and encrypted communications.
“We’re building a foundation for social communication aligned with the direction people increasingly care about: messaging each other privately,” he said in an interview at the time. “I believe a privacy-focused communications platform will become even more important than today’s open platforms.”
But regulators and lawmakers have been concerned that an integration may make it more difficult to disentangle the apps in the future. In July, Facebook disclosed that the F.T.C. was investigating it over antitrust concerns. The Justice Department, Congress and state attorneys general are also examining whether Facebook has acted anticompetitively.
Leading antitrust academics and others have laid out a case to regulators for breaking up Facebook by unraveling its acquisitions of Instagram and WhatsApp. They have argued that the company made “serial defensive acquisitions” to protect its dominant position in the market for social networks.
In practice, the back-end infrastructure of many Facebook properties has been shared for some time. Facebook and Instagram both use the same architecture to run their advertising businesses, for example.
Mike Isaac reported from San Francisco, and Cecilia Kang from Washington. Jack Nicas contributed reporting from San Francisco, and David McCabe from Washington.
This is a developing story and will be updated.