An endorsement that must be attached to the auto liability policy of certain
regulated motor carriers to ensure that federally mandated coverage (e.g.,
required liability limits and environmental restitution coverage) is in place.
The endorsement does not actually provide insurance except on a reimbursement
basis. For example, a standard unendorsed Insurance Services Office, Inc.
(ISO), commercial auto policy contains a pollution exclusion that would
preclude coverage for environmental restitution. In the event the broadened
pollution liability coverage endorsement (CA 99 48) is attached to a regulated
motor carrier's policy, the pollution exclusion is modified but not totally
deleted. In either event, if the MCS-90 endorsement is attached, the
insurer's obligation with respect to such a situation is determined by the
MCS-90 endorsement provisions regardless. If the policy would provide such
coverage even without that endorsement, the insurer pays the claim and the
endorsement effectively has no impact on the issue. However, if the claim would
not have been covered under the policy except for the MCS-90 endorsement
provisions, the insurer pays the claim and then has the right to seek
reimbursement from the insured.