Do Major Hurricane Landfalls Move Reinsurer Equity?

This paper is the tenth in the Conditional Probability of Exceedance (CPE) series (Ramanathan S, 2026a–2026i) and the first to test catastrophe-exposed reinsurer equity directly, motivated by a question raised in this research programme: whether instruments closer to a parametric, loss-driven payout structure show less market-sentiment noise between a physical event and price than the commodity channel tested in Paper 9. Using an event study around the 14 costliest US hurricane landfalls since 1995, tested by two independent methods — raw-return permutation testing and a market-adjusted (CAPM-style) exceedance retest built on a separately-constructed null distribution — this paper finds one validated result: a short-horizon loss reaction in RenaissanceRe (RNR), the sample's purest catastrophe-reinsurance pure-play, confirmed under both methods (raw-return p=0.0008; market-adjusted p=0.0015) and absent in a non-cat-exposed control group. A second hypothesis — a medium-horizon repricing reversal, initially apparent in Munich Re's raw returns (p=0.0046) — was tested under the same market-adjusted retest and did not replicate: its strongest result there was numerically indistinguishable from a hit of identical strength in a non-cat-exposed control ticker, the standard signature of multiple-testing noise rather than a real effect. It is reported here as a rejected hypothesis, not a finding. The validated result is narrower than this paper originally set out to establish, and, cross-confirmed by two methodologies built on different underlying return concepts, more trustworthy for it.