The Competition Bureau has, for at least a year, communicated that abuse of dominance is an enforcement priority. And, recently, the bureau has taken a more ambitious and aggressive approach in this arena as it challenges what it calls “anti-competitive” rules imposed by the Canadian Real Estate Association (CREA) on agents and consumers who list properties on its Multiple Listing Service (MLS).

The bureau's website says "abuse of a dominant position occurs when a dominant firm in a market, or a dominant group of firms, engages in conduct that is intended to eliminate or discipline a competitor or to deter future entry by new competitors, with the result that competition is prevented or lessened substantially."

And the tougher tactics being used are likely to affect corporate Canada.

"Dominant firms will be taking a closer look at their exclusivity arrangements, and vertically integrated companies will be taking a more analytical approach to unfairly increasing rivals' costs," says Eric Dufour, a partner in the Competition and Marketing Law Group in the Toronto office of Borden Ladner Gervais LLP.

"I've presented more compliance programs on abuse of dominance in the last 18 months than I did in the previous 10 years of practice," says Eric.