The justices, voting unanimously against UBS, said the 2002 Sarbanes-Oxley Act doesn't require whistleblowers to prove they were the victims of intentional retaliation. 

A whistleblower who invokes the relevant U.S. law bears the burden to prove that the protected activity was a contributing factor in their firing, but they are not required to make some further showing that the employer acted with retaliatory intent, the court said. 

Employees have filed more than 750 Sarbanes-Oxley claims with the Labor Department over the past six years. The law was enacted following the corporate fraud that toppled Enron Corp. and WorldCom Inc.

The Sarbanes-Oxley Act says employers may not "discriminate against an employee" because the worker reported financial wrongdoing.

UBS didn't immediately return an email seeking comment.

The case centered on Trevor Murray, who claimed he was fired for refusing to skew his reports to help the company's business strategies. A federal appeals court set aside a verdict in Murray's favor, saying he should have been required to prove that UBS intentionally retaliated against him. 

Murray worked in support of UBS's commercial mortgage-backed securities business. His suit described a "concerted, extended effort" by managers and colleagues to get him to write bullish assessments.

UBS said Murray's termination was part of a broader staffing reduction driven by the bank's financial difficulties at the time. UBS cited the impact of a $2 billion loss by a rogue trader at its London office five months before the firing.

Justice Sonia Sotomayor wrote the court's opinion.

The case is Murray v. UBS, 22-660.