Total return: 95%
Fortune 500 rank: 465
The telecom services company spent the better part of 2006 on a shopping spree. Wall Street seemed to endorse the move, as the stock nearly doubled in value.But while the acquisition strategy has given Level 3 new telecommunications infrastructure as it girds for competition against bigger rivals like Verizon and AT&T, it has also saddled the company in debt.
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