The applicant insurer sought a declaration that the respondent insurer was required to contribute equally to the defence and indemnification of a pharmacist in an underlying negligence action.
Both insurers had issued policies covering the pharmacist, and both policies contained 'other insurance' clauses stating their coverage was excess to any other valid insurance.
The court found that both policies provided primary coverage for the same risk at the same layer.
Applying the principles of equitable contribution, the court concluded that the competing 'other insurance' clauses were irreconcilable.
Consequently, the respondent was ordered to share equally in the costs of defending and indemnifying the insured.