Four tech companies are suing Facebook, accusing the Silicon Valley titan of running the worst “anti-competitive scheme” in a generation and demanding that CEO Mark Zuckerberg give up his stake in the company.

The four companies are Beehive Biometric, an identity-verification website; Cir.cl, an online marketplace and social media platform; Lenddo, a Singapore-based financial services provider; and Reveal Chat, a messaging service.

In a federal lawsuit filed in San Francisco on Thursday, the firms accuse Facebook of running “the most brazen, willful, anticompetitive scheme in a generation” throughout the last decade. (RT)