ABSTRACT A discrete‐time option‐pricing model is used to derive the “fair” rate of return for the property‐liability insurance firm. The rationale for the use of this model is that the financial claims of shareholders, policyholders, and tax authorities can be modeled as European options written on the income generated by the insurer's asset portfolio. This portfolio consists mostly of traded financial assets and is therefore relatively easy to value. By setting the value of the shareholders' option equal to the initial surplus, an implicit solution for the fair insurance price may be derived. Unlike previous insurance regulatory models, this approach addresses the ruin probability of the insurer, as well as nonlinear tax effects.

Insurance contracts are often complex and difficult to verify outside the insurance relation. We show that standard one-period insurance policies with an upper limit and a deductible are the optimal incentive-compatible contracts in a competitive market with repeated interaction. Optimal group insurance policies involve a joint upper limit and individual deductibles; insurance brokers can play a role implementing such contracts for their clients. Our model provides new insights and predictions about the determinants of insurance.