Stockholders' Equity

12 Months Ended

Dec. 31, 2012

Stockholders' Equity

Stockholders' Equity

K.    Stockholders' Equity

Preferred Stock

        Our certificate of incorporation authorizes our Board to issue preferred stock from time to time in one or more series. The rights, preferences, restrictions, qualifications and limitations of such stock are determined by our Board. In September 2009, our Board adopted a shareholder rights plan, or Rights Plan. The terms of the Rights Plan provide for a dividend distribution of one preferred share purchase right, or Right, for each outstanding share of our common stock, par value $0.01 per share, to shareholders of record as of September 17, 2009, and for one such Right to attach to each newly issued share of common stock thereafter. Each Right entitles shareholders to purchase one one-thousandth of a share of Series A Junior Participating Preferred Stock for each outstanding share of our common stock. The Rights issued pursuant to our Rights Plan become exercisable generally upon the earlier of 10 days after a person or group, or an Acquiring Person, acquires 20% or more of our outstanding common stock or 10 business days after the announcement by a person or group of an intention to acquire 20% of our outstanding common stock via tender offer or similar transaction. In that event, each holder of a Right, other than the Acquiring Person, would for a period of 60 days be entitled to purchase, at the exercise price of the Right, such number of shares of our common stock having a current value of twice the exercise price of the Right. Once a person becomes an Acquiring Person, until such Acquiring Person acquires 50% or more of our common stock, our Board can exchange the Rights, in part or in whole, for our common stock at an exchange ratio of one share of common stock per Right. If we are acquired in a merger or other business combination transaction, each holder of a Right, other than the Acquiring Person, would then be entitled to purchase, at the exercise price of the Right, such number of shares of the acquiring company's common stock having a current value of twice the exercise price of the Right. The Board may redeem the Rights or terminate the Rights Plan at any time before a person or group becomes an Acquiring Person. The Rights will expire on September 17, 2019 unless the Rights are earlier redeemed or exchanged by us. In May 2012, we amended the definition of an Acquiring Person in the Rights Plan to provide that Adage Capital Management, L.P., or Adage, would not be deemed an "Acquiring Person" unless Adage, together with its affiliates and associates, have acquired beneficial ownership of 25% or more of our outstanding common stock (other than solely from repurchases of stock by us which increases Adage's percentage ownership above 25%). Pursuant to the terms of the amendment, this provision terminated in the third quarter of 2012 and Adage returned to being subject to the 20% limit applied to our other stockholders.

Common Stock Transactions

        In January 2010, we sold 3,600,000 shares of our common stock, $0.01 par value per share, in an underwritten public offering at a price to the public of $48.25 per common share, resulting in gross proceeds of approximately $173.7 million. Net proceeds to us after deducting fees, commissions and other expenses related to the offering were approximately $165.6 million. The shares were issued pursuant to a shelf registration statement on Form S-3 which became effective upon filing.