This article asks whether the abandonment of drifting fish aggregating devices (dFADs) is illegal under international marine pollution law. To answer this question, it provides a brief overview of the general international legal framework for the protection of the marine environment as well as specific legal regimes, namely the London Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (LC), its 1996 Protocol (LP), and Annex V of the International Convention for the Prevention of Pollution from Ships (MARPOL). The article concludes that the abandonment of dFADs contravenes the LC/LP and/or, depending on the preferred interpretation, MARPOL Annex V. The decision as to which of the two regimes is applicable depends on whether dFAD abandonment can be classified as ‘incidental to, or derived from the normal operations of vessels … and their equipment’ or not. The negligent loss of dFADs always violates MARPOL Annex V. The article also shows that certain state practice and opinio juris suggests a parallel applicability of the two regimes with respect to deliberate dFAD abandonment. While such a development would ensure more comprehensive coverage of the relevant standards and prohibitions, a clear regulatory decision as to which of the two regimes is the correct one would be preferable from an implementation and enforcement perspective.