The Ontario Court of Appeal has given the green light to a $150 million class action lawsuit against Toronto-Dominion Bank over allegations of undisclosed and unauthorized fees to Visa cardholders.

The case arises over fees on Visa transactions in foreign currencies between 1986 and 2003.

Ontario Chief Justice Warren Winkler’s decision overturned a lower court ruling that blocked class-action status for the litigation.

“This decision is of fundamental importance to TD Visa cardholders as class members and to the public,” plaintiff lawyer Harvey Strosberg stated.

“The Court of Appeal recognized the necessity of allowing a class action against a financial institution which allegedly repeatedly overcharged some of its customers’ small amounts of money totalling tens of millions of dollars,” Strosberg said.

The bank could seek to appeal the latest decision to the Supreme Court of Canada.