Cogeris to Offer Comprehensive Insurance Tailored to Physicians St. Louis, MO. December 12, 2014 – Today, the board of directors of Keystone Mutual Insurance, a St. Louis-based medical malpractice insurance company, announced its alliance with a newly launched insurance agency, Cogeris Insurance Group. In addition to Keystone Mutual as the preferred med-mal insurance, Cogeris offers a full portfolio of insurance…