NEW YORK, June 3, 2013 /PRNewswire/ -- Pershing Square Capital Management, L.P. announced today that it plans to sell up to seven million common shares of Canadian Pacific Railway Limited (TSX: CP; NYSE: CP). Pershing Square plans to limit these sales to unsolicited brokers' transactions on the NYSE and the TSX in amounts that will not exceed 10% of the combined NYSE and TSX volume for the CP common shares on any day of trading. The sales will begin on or after June 10, 2013 and will likely be completed over the next six to twelve months. Pershing Square CEO Bill Ackman said: "Thanks to Hunter Harrison's and the CP team's performance over the last nearly one year, Canadian Pacific's share price has more than tripled since we first invested in CP. As a result, our stake in CP has grown to approximately 26% of the combined assets of our funds. Given that increased concentration, portfolio management considerations have driven our decision to trim our holdings. Even after these sales, we expect to remain CP's largest shareholder and for CP to remain one of our largest investments." Pershing Square's representatives, Bill Ackman and Paul Hilal, will continue to serve on the company's board of directors. They were elected to the board in May 2012 after successfully nominating a slate of directors as part of a proxy contest. Shortly thereafter, the company appointed rail industry veteran Hunter Harrison as its CEO. "We can't overstate our appreciation for Canadian Pacific's employees and the important contributions of our fellow board members," said Paul Hilal. Under Canadian rules, Pershing Square will make filings within three days following sale transactions, disclosing the price and number of shares sold.