The extant DEA estimation of efficiency presupposes the existence of a monotone strictly convex production function. The presence of increasing or decreasing returns to scale are two cases of scale inefficiency where the firm are producing at sub-optimal scales. The convex DEA framework is, however, in conflict with the S-shaped production function introduced by Ragnar Frisch. The present study provides an empirical investigation of life insurer efficiency using the cluster-based approach introduced by Tone and Tsutsui. The present study thus estimates and explains the cluster adjusted efficiency scores of Indian life insurers.