When Detours Fail: Chokepoint Closures, Bypass-Route Disruption, and the Equity-Market Pricing of Supply-Chain Exposure, 2023–2026

We examine how equity markets price firms’ exposure to maritime chokepoint disruptions when the bypass routes themselves become impaired. The paper develops a 2023–2026 event-study and panel framework centered on the Strait of Hormuz, the Red Sea/Bab el-Mandeb corridor, and Saudi Arabia’s East-West Pipeline. We distinguish primary-route exposure from detour vulnerability through a Dual Chokepoint Exposure Index (DCEI) and an Independent Deliverable Capacity (IDC) measure that discounts nominal bypass capacity for terminal, vessel, insurance, inventory, transfer, and onward-route constraints. The design tests abnormal returns and volatility around route-disruption events; identifies a detour-failure premium by comparing primary-closure events with the 20 July 2026 Saudi port-navigation ban and the 10–11 September 2026 East-West Pipeline disruption; traces subsequent changes in cash holdings, inventories, trade credit, leverage, and capital expenditure; and models customer–supplier contagion through network-adjusted exposure. Documented evidence from 2023–2026 shows that maritime stress shifted rather than disappeared as trade was rerouted and that restoration of bypass capacity carried market-relevant information. The framework connects supply-chain resilience to asset pricing and corporate finance by treating independent deliverability—not nominal redundancy—as the financially relevant hedge against chokepoint risk.