Classification societies define technical and safety standards for ships and assign class notations to indicate a ship's risk for insurers. Classing a ship ensures it meets requirements, may lower insurance costs, shows due diligence in maintenance, and protects investments. Major classification societies include Lloyd's Register, American Bureau of Shipping, Bureau Veritas, Det Norske Veritas, and others. They survey ships for compliance with design, construction, and maintenance rules and certify that vessels are in class and meet standards.