What is the ruling on working for a marine surveying company that investigates ship accidents and supervises the unloading of cargo, and relies in its work on foreign insurance companies?

There is no objection to a marine surveying company working for insurance companies, as long as the required work is permissible, such as investigating accidents and supervising the unloading of goods. This falls under the category of dealing in permissible matters with those who engage in forbidden contracts or whose wealth is mixed. The basis for its permissibility is the Prophet's (peace be upon him) and his companions' dealings with Jews and polytheists in buying, selling, and other matters, despite their wealth not being free from the unlawful. However, working for an insurance company itself or a branch thereof is not permissible, due to the prohibition of commercial insurance.