Whiting Petroleum Corporation (NYSE: WLL) announced today that it is exercising its right to convert all outstanding shares of its 6.25% convertible perpetual preferred stock (NYSE: WLLPrA) into shares of the Company's common stock effective as of 5:00 p.m. Eastern Time on June 27, 2013. The preferred stock contains provisions that allow Whiting to mandatorily convert the preferred stock into common stock after June 15, 2013 if the common stock closes above $26.05 per share for at least 20 trading days in a period of 30 consecutive trading days, which was satisfied at the close of trading on the New York Stock Exchange on June 14, 2013. Each share of preferred stock has a liquidation preference of $100.00 per share and converts into shares of common stock based on the current conversion price of $21.70815, which equates to approximately 4.6066 shares of common stock for each share of preferred stock. If fractional shares result from the mandatory conversion, Whiting will make a cash payment based on the closing sale price of Whiting’s common stock on June 25, 2013. As of June 14, 2013 there were 172,129 shares of preferred stock outstanding, which Whiting expects to convert into approximately 792,900 shares of common stock. All outstanding shares of the preferred stock are held through the Depository Trust Company, whose nominee, Cede & Co., is the sole record holder of the preferred stock. On June 27, 2013, dividends on the preferred stock to be converted will cease to accrue and all rights of holders of such preferred stock shall terminate except for the right to receive whole shares of common stock issuable upon conversion and a cash payment for fractional shares. No action by beneficial holders is required. Immediately following the effective date of the mandatory conversion, the preferred stock will cease trading and will be delisted from the New York Stock Exchange.