PERSHING SQUARE CAPITAL MANAGEMENT
Headquarters: New York
CEO: William Ackman, 41
Holdings: Ackman has bumped up his stake in Target Corp. to 9.97 percent. In July, Pershing Square owned a 9.6 percent stake in Target.
Other investments: Barnes and Noble Inc., Borders Group Inc., McDonalds Corp. and Sears Holding Corp.
Previous holdings: Acquired nearly 21.4 million shares, or 15 percent, in Ceridian Corp., and helped push it into a merger last fall. Pershing Square acquired more than 5 percent of Wendy's International Inc. and pushed it to spin off its Canadian doughnut subsidiary, Tim Horton's Inc.
