Index insurance is often proposed to reduce protection gaps, especially for emerging risks. Unlike traditional insurance, it bases compensation on a measurable index, enabling faster payouts and lower claim management costs. This approach benefits both policyholders, through quick payments, and insurers, through reduced costs and better risk control due to reliable data and robust statistical estimates. An important difference with the concept of Cat Bonds is that the feasibility of such coverage relies on the possibility of mutualization. Mutualization, in turn, is achieved only if a sufficiently high number of policyholders agree to subscribe. The purpose of this paper is to introduce a model for the demand for index insurance and to provide conditions under which the solvency of the portfolio is achieved. From these conditions, we deduce a product that combines index and traditional indemnity insurance in order to benefit from the best of both approaches. We illustrate our results with a practical example involving the design of an index insurance product in the field of cyber insurance.

翻译：指数保险常被提议用于缩小保障缺口，尤其针对新兴风险。与传统保险不同，其赔付基于可测量的指数，从而实现更快速的理赔支付和更低的索赔管理成本。这种方法通过快速赔付使投保人受益，同时借助可靠数据和稳健的统计估计，通过降低成本和优化风险控制使保险公司受益。与巨灾债券概念的一个重要区别在于，此类保险的可行性依赖于风险共担的可能性。而风险共担的实现，仅当足够多的投保人同意参保时才能达成。本文旨在构建指数保险的需求模型，并提供实现投资组合偿付能力的条件。基于这些条件，我们推导出一种融合指数保险与传统赔偿保险的产品，以兼收两种方案的优势。我们通过网络安全保险领域设计指数保险产品的实际案例来阐释研究结果。