Fish aggregating devices (FADs) are widely used in artisanal fisheries in the Mediterranean Sea and in tropical tuna fisheries. Thousands of FADs are lost or abandoned each year, with many causing environmental damage. This article examines whether such loss or abandonment contravenes international marine pollution law. It finds that abandonment probably constitutes “dumping” within the meaning of the international dumping regime and thus, depending on the material of which a FAD is made, is either prohibited or subject to a permit system, and that the nonaccidental loss of a FAD breaches Annex V of MARPOL. The article also considers what action may be taken against the flag states of vessels that have abandoned or lost FADs.