The Quebec agency that runs Montreal's Olympic Stadium is suing the U.S. company that was hired to install its roof last winter.
Birdair of Amherst, New York was putting up the $37 million roof when it caved in, showering the stadium's floor with snow.
Workers inside had been setting up for a car show.
No one was injured in the incident but the Olympic Stadium's Installation Board is suing because it had to cancel car and boat shows at the facility after the roof was damaged.
The Board is also suing Birdair for the costs of inspectors for the roof following the tear.