Both Icahn (Netflix, Clorox) and Southeastern (Vulcan Materials, Olympus) are experienced corporate gadflies.

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Vulcan Materials Co shares are currently trading down about 1.9% on the day.

FORBES: Vulcan Materials Stock Getting Very Oversold

Vulcan Materials Co shares are currently trading off about 1.4% on the day.

FORBES: VMC Stock Crowded With Sellers

Vulcan Materials (VMC) is expected to book a narrower loss than a year ago when it reports fourth quarter earnings on Thursday, February 14, 2013 with analysts expecting a loss of 10 cents per share, up from a loss of 14 cents per share a year ago.

FORBES: Earnings Preview: Vulcan Materials