Golden Finance reports that the latest documents show that Buffett’s Berkshire Hathaway purchased 143,424 shares of the Internet infrastructure services company VeriSign for an additional US$28.55 million in the three trading days ending on the 24th. ) stocks. Including the stocks it has purchased previously, Berkshire currently holds a total of 13.7% of VeriSign's issued shares, worth nearly US$2.7 billion. According to reports, one reason why Buffett is interested in VeriSign may be that it ranks high in various profit margin indicators among S&P 500 companies.