Credits: ÉRIC BEAUPRÉ/QMI AGENCY
The suit covers one million customers who filled up at gas stations in Quebec City, Trois-Rivieres and Drummondville, among other cities.
The Montreal-based Automobile Protection Association (APA) launched the suit, which Judge Dominique Belanger approved Friday.
Clients who filled up between Jan. 1, 2002, and June 30, 2006, can apply for potential compensation.
The allegations in the lawsuit haven't been proven in court.
A number of lawsuits against big oil companies were launched following a Competition Bureau investigation into gasoline pricing in Quebec.
Wiretaps revealed a number of stations called each other to fix prices at specific times.
Economists noted that gas prices fell across eastern Quebec after the bureau announced its probe.
Earlier this year, three gas retailers in eastern Ontario pleaded guilty to price-fixing and were fined more than $2 million.