Six more hedge funds joined a lawsuit against Porsche SE over alleged securities fraud and manipulation last week, with the plaintiffs doubling the damages they are seeking to $2bn.

The 35 individual funds controlled by the 10 investors listed in the lawsuit say Porsche SE aimed to trigger a massive short squeeze late in October 2008 in order to sell into the highs and rake in billions that helped rescue the automotive group from near-bankruptcy.

"Porsche SE collected outrageous profits at the expense of plaintiffs," the funds added.

The investors involved include Canyon Capital, D.E. Shaw, Greenlight Capital, Ironbound Partners, Royal Capital and Tiger Global, which joined the existing group comprising of Glenhill Capital, Elliott Associates, Glenview Capital and Perry Partners, the plaintiffs' spokeswoman said.