The lawsuit – filed by Elliott Associates, Glenhill Capital Management, Glenview Capital Management and Perry Capital – was lodged in a Manhattan federal court yesterday. It alleged that Porsche and former chief executive Wendelin Wiedeking and former vice president of finance Holger Haerter “repeatedly misled investors and lied about Porsche’s positions and intentions with respect to VW”.
A further 50 claimants could join the suit, pushing its value to $10bn.
A spokesman for Porsche said it “always abided by current capital markets law”.
VW shares briefly topped €1,000 (£871) apiece in 2008 – making Volkswagen the world’s most valuable company – during Porsche’s prolonged pursuit of its mass market Germany rival.
Saddled with debt just as global markets collapsed, Porsche last year abandoned the takeover attempt for its much larger rival and agreed to pursue a merger that is supposed to complete next year.