Update (Dec. 20, 2011) - On December 20, 2011, Vulcan Materials Company filed a countersuit against Martin Marietta Materials over allegedly unlawfully using confidential information.

San Diego, Dec. 13, 2011 (Shareholders Foundation) -- Following the announcement by Martin Marietta Materials that it intends to acquire Vulcan Materials Company and that it filed a lawsuit against Vulcan Materials prompted an investigation for investors in shares of Vulcan Materials Company (NYSE:VMC) concerning whether the offer to acquire Vulcan Materials Company is unfair to NYSE: VMC investors and whether certain of its officers and directors breached their fiduciary duties.

The investigations by law firms concern whether certain of its officers and directors breached their fiduciary duties owed Vulcan Materials (NYSE:VMC) investors in connection with the takeover offer.

On Monday, December 12, 2011, Martin Marietta Materials, Inc. (NYSE: MLM) announced that it has delivered an unsolicited proposal to Vulcan Materials Company (NYSE: VMC) and commenced an exchange offer to effect a business combination with Vulcan Materials. Under the terms of the proposed offer, each outstanding share of Vulcan Materials Company (NYSE: VMC) would be exchanged for 0.50 Martin Marietta Materials, Inc. (NYSE: MLM) shares or for a value of approximately $36.69 per share based on the previous trading days closing prices.

Martin Marietta Materials, Inc. said the offer the offer represents a premium for Vulcan shareholders of 15% to the average exchange ratio based on the closing share prices for Vulcan Materials Company (NYSE: VMC) and Martin Marietta Materials, Inc. (NYSE: MLM) during the 10-day period ended December 9, 2011 and 18% to the average exchange ratio based on the closing share prices for Vulcan Materials Company (NYSE: VMC) and Martin Marietta Materials, Inc. (NYSE: MLM) during the 30-day period ended December 9, 2011.

Martin Marietta Materials also said it filed a lawsuit in connection with the takeover offer in Delaware Chancery Court and a lawsuit in New Jersey state court.

However, following the announcement NYSE VMC stocks jumped on December 12 from as low as $31.97 per share to as high as $42.19 per share and closed on Monday at $38.75 per share, both well above the current offer. In addition, shares of Vulcan Materials Company (NYSE:VMC) traded during early 2011 as high as $46.73 per share and during 2010 as high as $57.28 per share, and at least one analyst has set the high target price for NYSE VMC stocks at $49 per share.

Furthermore, Vulcan Materials performance increased lately. Its third quarter Revenue rose from $743.20million last year to $760.75million this year and its third quarter Net Income increased from $13.25million a year ago to $19.96million this year.

Therefore the investigation for VMC investors concerns whether the Vulcan Materials Board of Directors will undertake an adequate sales process and in particular adequately shop the Company before entering into any transaction. A potential securities class action lawsuit would seek to maximize the amount of money and information Vulcan Materials Company (NYSE:VMC) shareholders would receive in a buyout, so the law firm.