Restating its oil reserves has caused Shell a number of problems

The investors hold about 5% of Shell's shares and are reported to be seeking $150m (£85m) in damages.

The legal action is the latest to hit Shell after the firm admitted it had overstated reserves by more than 20%.

Royal Dutch Shell shares tumbled after the news broke at the start of last year, causing great investor anger.

Fight the claims

In the selling blitz that followed the announcement, $15bn was knocked off the company's market value.

Shell already has agreed to pay out some compensation to settle other legal actions, and last year merged its Dutch and UK operations in an effort to revamp its business and win back investor trust.

The latest lawsuit was brought by pension funds, including Stichting Pensioenfonds ABP, one of Europe's biggest.

It was filed in New Jersey and names both current and former Shell staff, including chief executive Jeroen van der Veer.

Shell is accused of making "materially false and misleading statements".

The oil company denied the claims made in the latest lawsuit and said it would "vigorously" defend itself.