Separate wordings that buy back, in a distinct market and on seven days notice, the war and strikes perils excluded from base marine policies.
Base marine policies, hull and cargo alike, exclude war, civil war, capture, seizure, derelict mines and weapons, together with strikes, riots and civil commotions. The Institute War and Strikes Clauses write those perils back as standalone wordings, placed with specialist underwriters and rated separately, per transit for cargo and per period for hull. Their distinctive feature is reversibility: the underwriter can cancel on seven days notice, cut to forty-eight hours for the nuclear peril, and cover terminates automatically on open conflict between the major powers. Rating follows the list of areas published by the London Joint War Committee, each revision of which reads straight through to the premiums on the affected transits. The problem solved is a peril whose probability changes from one day to the next on a political decision, and which a premium fixed twelve months earlier cannot reflect.
After the Joint War Committee extended its listed areas to the southern Red Sea and the Gulf of Aden in late 2023, hull war premium moved from about 0.02% of the ship's value to close to 0.7% by the spring of 2024, several hundred thousand dollars for a single transit, and some owners preferred the extra 3,500 miles around the Cape of Good Hope.
garantie risque de guerre et grèves, IWC