An appreciation of the part played by marine insurance is essential to an understanding of the shipping industry and the special law that governs it. Most shipowners carry hull insurance on their ships and protect themselves against claims by third parties by means of “protection and indemnity” insurance. Waterborne cargo is almost universally insured against the perils of the seas. It is impossible in a brief outline such as this to go into any of the special intricacies, which are many, of marine insurance law. Most cases of damage to a ship or its cargo resolve themselves into settlements between insurance carriers. Proposals for changes in the maritime law must always be evaluated against this background of insurance coverage, as the imposition of liabilities that cannot be insured against can discourage all but the wealthiest ocean carriers from engaging in the affected trades.

Marine insurance is the oldest known form of insurance. Indeed, the institution of general average, under which the participants in a maritime venture contribute to losses incurred by some for the benefit of all, may itself be looked on as a primitive form of mutual insurance. Hull and cargo insurance today, in fact, is usually written on forms whose wording has changed little since the 18th century. The so-called “perils” clause, enumerating the risks insured against, customarily includes not only the natural hazards to which a vessel is exposed but man-made perils such as capture or destruction by enemy forces as well. In 1898, however, Lloyd’s of London underwriters inaugurated the practice of adding “Free of Capture and Seizure” (F.C.&S.) clauses to the basic policy forms, the effect of which was to remove war and similar risks from coverage. The practice has since become universal, with the result that the owner of a ship or cargo must either purchase separate war-risk insurance or else pay his marine underwriters an additional premium in return for deletion of the F.C.&S. clause.

An early type of marine liability insurance was against liability for damage that the insured vessel caused to other vessels. Such insurance was effected by the addition of a “running down” or “collision” clause to the basic hull policy insuring the owner or operator of a vessel against its loss or damage. On the theory that, if given full protection, owners and operators would not be encouraged to exercise proper care in the maintenance of their vessels and the selection of their masters and crews, hull underwriters at first refused to insure against more than 75 percent of the collision liability.

With the advent of steam-driven vessels of iron and steel in the 19th century, the potential liabilities of shipowners increased substantially. To protect themselves, British owners banded together in “protection and indemnity” associations, commonly known as “P. and I. Clubs,” whereby they insured each other against the liabilities to which they were all exposed in the operation of their vessels. These included liability for cargo damage, personal injury, and damage to piers, bridges, and other fixed objects, and also 25 percent of the liability for damage to other vessels against which the hull underwriters refused to insure. Foreign owners soon found the P. and I. Clubs attractive, and as of 1973 the operators of about 80 percent of the world’s ocean tonnage were insured with the British clubs and their Scandinavian and Japanese affiliates.