GREENWICH, Conn.--(BUSINESS WIRE)--W. R. Berkley Corporation (NYSE: WRB) announced today that its Board of Directors has increased the Company's share repurchase authorization to 25 million shares of common stock. The Company's focus continues to be on delivering value to shareholders through building book value as well as returning excess capital to shareholders through a variety of available methods. Repurchases may be made by the Company from time to time at prevailing prices in the open market or in pri ...