Warren Buffett's Berkshire Hathaway has long held a position in VeriSign (VRSN 1.54%). The company first began acquiring shares in 2012. It made the bulk of its purchases from 2012 to 2014 but had periodically trimmed its position until late last year, when it suddenly began repurchasing shares in December. Berkshire has earned massive gains in the stock in its 13-year history of holding shares, but the sudden resurgence in interest comes as a surprise. Given this activity, should investors follow the lead ...