Monday’s sentencing of plaintiffs’ attorney Mel Weiss to two-and-a-half years in prison for paying secret kickbacks to some of his investor clients marks the end of an era for US class action lawsuits.

At its peak, Mr Weiss’s former firm Milberg Weiss served as lead attorneys in more than 50 per cent of US class action securities cases and won billions of dollars in settlements for disgruntled investors.