Activist investing takes places in even the largest multinational firms, as was the case with Bill Ackman of Pershing Square Capital Management, who forced McDonald's (MCD) - Get Report to make vital changes to its menu, improve customer service and realize hidden real estate value, all of which ultimately led to a doubling in McDonald's stock price.

Another large multinational firm engaged with an activist investor is

Yahoo!

(YHOO)

. Now-board-member

Carl Icahn

has so far been unsuccessful in his attempts to get Yahoo! to sell its search business -- or even the entire company -- to

Microsoft

(MSFT) - Get Report

.

But sometimes the activist investor isn't just another hedge fund. Take

GSI Group

(GSIG)

. Stephen W. Bershad, the CEO of

Axsys Technologies

( AXYS), put his own capital on the line when he recently bought 3.3 million shares of GSI Group in the open market.

To read more,

visit Stockpickr.com

.

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