Of course the US stock went up and the Canadian stock went down - you could buy the shares in US dollars for $17 a pop, sell them in Canadian dollars for over $

Of course the US stock went up and the Canadian stock went down - you could buy the shares in US dollars for $17 a pop, sell them in Canadian dollars for over $30 and then convert back to US dollars at a rate of about $1.20 per Canadian dollar and wind up with a tidy profit of $8+ a pop or 50%+. They should have set the IPO price in one currency and the price on the other exchange as a function of the noon rate the previous day. Any deviation from a price in one currency that is the exchange rate * the price in the other currency plus or minus transaction costs will be exploited by arbitrageurs.