Oct 6 (Reuters) - A former partner at Pershing Square Capital Management is preparing to launch a new fund, according to a U.S. regulatory filing.
Paul Hilal, who left Pershing Square in January, is launching Mantle Ridge LP, a New York-based investment fund, the filing said.
Hilal was a close lieutenant to Pershing's founder, William Ackman, and was a driving force behind the activist fund's investment in railway operator Canadian Pacific Railway Ltd .
Hilal did not immediately return an email seeking comment. (Reporting by Michael Flaherty in New York; Editing by Lisa Shumaker)