The Defense Department Group Term Insurance Plan is available for contractor use under cost-reimbursement type contracts when approved as provided in department or agency regulations. A contractor is eligible if—

(a) The number of covered employees is 500 or more; and

(b) The contractor has all cost-reimbursement contracts; or

(c) At least 90 percent of the payroll for contractor operations to be covered by the Plan is under cost-reimbursement contracts.