Insurance protecting a group of persons, usually employees of the same firm. It is based on the principle that the selection process may be applied directly to groups of people, as well as to individuals. If certain general requirements are met, the insurance principles can be applied to groups of nonselected persons. As a rule, the group must have been formed for a purpose other than to obtain insurance; the members must either all be insured or, if premiums are paid in part by the individuals, at least 75% must become insured; the amount of insurance for each member of the group must be determined by a formula precluding individual selection or choice by the individuals insured.