Which principle states that if an insurer accepts a practice for a time, it cannot later refuse coverage based on that practice?

The principle that states if an insurer accepts a practice for a time, it cannot later refuse coverage based on that practice is known as estoppel. Estoppel is a legal doctrine that prevents a party from arguing something contrary to a claim they previously made when another party has relied on that original claim to their detriment. In the context of insurance, if an insurer has consistently accepted certain practices or conditions without objection, they cannot later deny coverage based on those same practices. This principle helps to maintain fairness and prevents insurers from changing their positions arbitrarily, which could lead to confusion and loss for policyholders who rely on established practices.

Indemnity relates to compensating for losses and is not connected to the acceptance of practices over time. Subrogation involves the right of an insurer to pursue a third party that caused an insurance loss to recover the amount of the claim paid to the insured, and it does not pertain to the acceptance of practices. Underwriting is the process insurers use to evaluate the risk of insuring a potential policyholder and also does not involve the acceptance of practices after the fact.