On Thursday, Hughes called for the breakup of Facebook in an op-ed in The New York Times. Hughes said he's concerned that Zuckerberg has surrounded himself with a team that doesn't challenge him. So it falls on the government to hold him accountable and curb his "unchecked power." Along with overseeing Facebook, Instagram and WhatsApp, Zuckerberg controls 60% of voting shares on Facebook's board, according to Hughes.
"We are a nation with a tradition of reining in monopolies, no matter how well-intentioned the leaders of these companies may be. Mark's power is unprecedented and un-American," Hughes said in the op-ed.
In an emailed statement, Nick Clegg, Facebook's vice president of global affairs and communications, said the company accepts that with success comes accountability.
"You don't enforce accountability by calling for the breakup of a successful American company," Clegg said. "Accountability of tech companies can only be achieved through the painstaking introduction of new rules for the internet. That is exactly what Mark Zuckerberg has called for."
Hughes said the Federal Trade Commission made a mistake in letting Facebook acquire Instagram and WhatsApp -- and now time is running out to easily fix that.
"Until recently, WhatsApp and Instagram were administered as independent platforms inside the parent company, so that should make the process easier," Hughes said. "But time is of the essence: Facebook is working quickly to integrate the three, which would make it harder for the FTC to split them up."
Even with a breakup, Hughes said, Facebook will still be profitable.
And breaking up Facebook isn't even enough, said Hughes, who left the company in 2007. The co-founder called for a new agency to ensure tech companies protect privacy and to create guidelines for acceptable speech on social media. Hughes added that even if a breakup isn't successful, pushing for one would at least bring more oversight.
"I take responsibility for not sounding the alarm earlier," he said.
Originally published May 9, 6:19 a.m. PT.
Update, 10:15 a.m.: Adds statement from Facebook.