Houston’s Vinson & Elkins, longtime outside counsel for Enron Corp., was dismissed from a massive shareholder securities class action filed by disgruntled Enron shareholders.

In an order signed Wednesday, U.S. District Judge Melinda Harmon of Houston dismissed a number of other defendants from the class action, which is set for trial in April, including former Enron executives Lou Pai, Kenneth Rice, Joseph Hirko, Kevin Hannon and Lawrence Greg Whalley. She also dismissed the estate of former Enron Chairman Kenneth Lay, who died in July 2006 after he was convicted in federal court of criminal charges stemming from the collapse of Enron.