HANOVER INSURANCE <HINS> GET SPLIT APPROVAL Hanover Insurance Co said its stockholders approved a two-for-one stock split. As a result of the split, Hanover said it increases the number of authorized shares of capital stock from 10.4 mln, having a par value of one dlr, to 20.9 mln, also having a par value of one dlr. The stock split is payable April 30 to stockholders of record April 10, Hanover said.