Last year a court ruled that the lenders, which include Brigade Capital Management LP, HPS Investment Partners LLC and Symphony Asset Management, were not required to return the $504m (£430m) to Citigroup, Bloomberg reports.

Citigroup’s successful appeal of the ruling is “a great win” for the firm’s main banking unit allowing them some redemption over the “massive unforced error”. The mistake comes as an example that highlights the need for manual processes to be automated.

A Citigroup spokesperson said:  “Today’s ruling reaffirms our long-held belief that these mistakenly transferred funds should be returned as a matter of law, as well as ethics.

“While Citi has taken steps to reduce the likelihood of such an error in the future, today’s decision provides welcome stability and upholds the concept of cooperation needed for a well-functioning syndicated lending market.”

Eric Talley, a Columbia Law School professor and specialist in corporate law and finance, said the judges “got to the right outcome” but added that “the delay was considerable and costly.”