Dec. 21 (Bloomberg Law) -- A recent spate of cross-border mergers involving Canadian law firms present challenges for those involved, as well as opportunities, according to law firm consultant Jordan Furlong. With only about 10 Fortune 500 companies based in Canada, the country's BigLaw market is driven by trade, and firms are scrambling for a global footprint, says Furlong, a consultant at Edge International and Stem Legal Web Enterprises. The risk is that many Canadian BigLaw firms get lots of business from U.S. firms, and merging with any one of them -- as Norton Rose has done with the United States' Fulbright & Jaworski -- may make work from other U.S. firms dry up. There are rumors of more cross-border mergers in the offing, he says, but if any of the country's very top firms take the plunge "then all bets are off. It will turn the market upside down," he says.