William Felix Browder is an Americanborn British financier and political activist He is the CEO and cofounder of Hermitage Capital Management the investment advisor to the Hermitage Fund which at one time was the largest foreign portfolio investor in Russia The primary investment strategy of Browder was shareholder rights activism Browder took on large Russian companies such as Gazprom Surgutneftegaz Unified Energy Systems and Sidanco In retaliation on November 13 2005 Browder was refused entry to Russia deported to the UK and declared a threat to Russian national security