The shadow fleet consists primarily of tankers used to circumvent international sanctions and regulations by concealing ownership, flag, and sometimes lacking Western insurance, multiple reports indicate. The ships are often registered in companies in countries other than Russia, and their legal domicile is changed by being registered in other countries' ship registers. It is unclear which specific international sanctions and regulations are being circumvented or which countries are used for registration.
The ships are often older models, lack proper maintenance, and are operated by companies in countries with weak regulations to avoid costs, safety regulations, and compliance with sanctions. The shadow fleet poses an environmental and safety risk, though the specific risks and whether any incidents have occurred are not detailed. The number of ships in the fleet and their total capacity remain unknown, as do the identities of the operating companies and their connections to Russia.