“You could make the argument that there is not much overlap between the two networks and between their businesses,” said Jim Corridore, head of industrials equity research at Standard & Poor’s. “But they would face significant hurdles of getting a merger passed by the U.S. Any merger would require STB approval. Shares of Canadian Pacific were not traded Monday in Canada as markets were closed for a holiday. They were up 1 percent in trade on the New York Stock Exchange.