What is the definition of a class and what is the effect of the definitions?

The chambers judge agreed with CIBC that the definitions proposed by the plaintiff were overbroad. After reviewing and distinguishing Arabi v. Toronto-Dominion Bank [2006] O.J. No. 2072 (S.C.J.), she suggested that a definition was required that would delineate the class “in terms of the time period during which those standard terms were applied to all mortgages and type of mortgage or prepayment”. She left it to counsel to make further submissions or agree upon an amended definition. In the meantime, the action was conditionally certified “pending the court being satisfied that the class has been properly narrowed and defined.” (Para. 116.)