Stocks listed on both NY exchange and CDN Exchange

[Theoneandonly]

Just wondering how they regulate the stock price if the stock is listed on both NY and Toronto stock markets. Or do they just let demand and supply determine the price in each market?

[pitz]

Arbitrageurs, with fast access to both order books, and a wholesale forex facility, keep the supply and demand for shares in balance so that the prices do not get out of whack.

Its basically an automated computer program they run. If shares are 'cheaper' on the NYSE than on the TSX, they go short the TSX traded shares, and go long the NYSE traded shares. At the end of the day, any imbalance is corrected by moving shares between the accounts to cover the positions.