An MCS-90 endorsement is an endorsement that must be attached to the auto-liability policy of some regulated car carriers to ensure mandatory federal coverage (such as required liability limits and environmental damage coverage) is in place. An endorsement does not actually provide insurance, except on an indemnity basis. For example, a standard non-approved commercial vehicle insurance policy from Office Insurance Services, Inc. (ISO) contains a pollution exclusion that excludes environmental damages coverage. If an extended pollution liability acknowledgment (CA 99 48) is attached to a regulated road carrier policy, the pollution exclusion is modified but not completely removed. In any event where an MCS-90 endorsement is attached, the obligations of the insurer in respect of such situation shall be determined by the provisions of the MCS-90 endorsement regardless. If the policy provides such coverage even without this approval, the insurer pays the claim and the approval does not actually affect the issue. However, if the claim would not have been covered by the policy, except under the MCS-90 confirmation provisions, the insurer pays the claim and then has the right to claim reimbursement from the policyholder.