The infamous court clashes between Cameron and Tyler Winklevoss and Facebook CEO Mark Zuckerberg aren't over yet.

The Winklevosses, as well as their business partner Divya Narendra, sued Zuckerberg in 2007 for allegedly stealing their idea for ConnectU—a social networking website for Harvard University students—and transforming it into Facebook. The legal battle came to a close with a settlement in 2008 in which the Winklevosses and Narendra received $20 million in cash and Facebook stock worth $45 million.

But the plaintiffs appealed the settlement, arguing that their compensation wasn't sufficient because Facebook's true value had been misrepresented during proceedings. In April, the 9th Circuit ruled that the settlement was adequate.

The Winklevoss twins and Narendra announced June 23 that they would drop their challenge to the 2008 settlement and not appeal it to the Supreme Court. However, according to the Wall Street Journal, they will pursue a separate lawsuit in a Massachusetts district court in which they claim Facebook suppressed evidence—specifically, instant message conversations between the Winklevosses and Zuckerberg dating back to 2004, when Facebook was founded—during the discovery phase of the 2008 settlement negotiations.

Facebook says the allegations are meritless and have already been rejected by the courts.