Massachusetts' two largest health insurers again are seeking double-digit increases in the rates charged to small businesses and individuals. Two months ago, the state Division of Insurance rejected 235 proposed premium increases that would have taken effect April 1, requiring insurance companies to continue billing customers at 2009 rates. The new round of proposed increases covers health plans coming up for renewal in the three-month period that starts July 1. Blue Cross Blue Shield of Massachusetts is requesting increases averaging 12%. Harvard Pilgrim Health Care wants increases that range from 8.8%-11.9%, the Boston Globe reports.