Boston/Montreal | Reuters — Billionaire U.S. investor William Ackman has exited his hedge fund’s investment in Canadian Pacific Railway, freeing up roughly US$1.5 billion in cash to make other future investments.

Pershing Square Capital Management and CP on Wednesday said the New York-based hedge fund had sold its remaining 9.8 million shares in the Canadian railroad, representing a 6.51 per cent stake, through trades organized by J.P. Morgan, Credit Suisse and BofA Merrill Lynch.

The sale marks the end of one of Ackman’s most profitable and successful investments, but comes at a time the prominent activist investor is facing double-digit losses in his highly concentrated investment portfolio.

Pershing Square began buying into the underperforming Calgary-based railroad around late September 2011 and mounted one of the hedge fund industry’s bitterest and most closely watched proxy battles, only to win seven seats on the company’s 16-member board in 2012.

In the end, Pershing Square earned some US$2.6 billion on its investment, and Ackman privately said winning the board contest would ensure that no company in the world could afford to ignore his firm.

Ackman said he plans to keep his board seat until the company’s next annual meeting. Earlier this year, Paul Hilal, a key architect of the investment, resigned his CP board seat when he left Pershing Square.

Pershing Square sold down its stake in CP earlier this year but told investors later that it still had full confidence in the railway’s management. Late last year, Ackman played a key role in CP’s efforts to buy rival railroad Norfolk Southern, an effort that eventually collapsed.

While CP will go down as one of Ackman’s big winners, he is currently known more for his fund’s losers — namely his investment in Laval, Que.-based Valeant Pharmaceuticals, which he made in 2015 and which has cost his investors billions in paper losses as the stock price crashed 91 per cent in the last 52 weeks.

Ackman’s exit from CP has some similarities to his exit three years from a losing bet on J.C. Penney; he relied on Citigroup to help him exit an 18 per cent position by selling 39.1 million shares.

— Reporting for Reuters by Allison Lampert and Svea Herbst-Bayliss.

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