Trisoko Sugeng Sulistyo*
Yos Johan Utama**
Aju Putrijanti***
Maritime Sanctions and Shadow Economy: Rethinking How Flag States Enforce Administrative Penalties on Dark Fleet Vessels
Suggested citation:
Sulistyo, T. S., Utama, Y. J., & Putrijanti, A. (2026). Maritime Sanctions and Shadow Economy: Rethinking How Flag States Enforce Administrative Penalties on Dark Fleet Vessels. Lex Portus, 12(1), 36–54. https://doi.org/10.62821/lp12103
Published online: 21.02.2026
*Diponegoro University (Semarang, Indonesia)
**Diponegoro University (Semarang, Indonesia)
***Diponegoro University (Semarang, Indonesia)
ABSTRACT
The phenomenon of the dark fleet in the global maritime economy has escalated significantly following the imposition of international sanctions against Russia since 2022 and has developed into a systemic mechanism for evading sanctions that undermines the effectiveness of international maritime governance. This article analyzes the structural weaknesses in the enforcement of administrative sanctions by flag states against illegal vessels and their legal implications within the framework of monitoring obligations under the United Nations Convention on the Law of the Sea (UNCLOS). The research uses a normative legal approach with qualitative analysis of UNCLOS, international maritime conventions such as SOLAS and MARPOL, international sanctions regimes, and maritime investigative reports. The results of the study show that the practices of open registries and flags of convenience are systematically exploited for flag-hopping, beneficial ownership concealment, Automatic Identification System (AIS) switching off, and ship-to-ship transfers that create maritime zones of impunity. The repeated failure of flag states to carry out their due diligence obligations as stipulated in Article 94 of UNCLOS could potentially be classified as a violation of international obligations that triggers state responsibility. This article emphasizes the need for structural reform through the strengthening of port state control, the adoption of advanced surveillance technology, binding ship ownership transparency, and the updating of global flag registration standards to restore the effectiveness of maritime sanctions enforcement and the integrity of international maritime law.
Keywords: sanctions, shadow fleet, dark fleet, flag state, administrative enforcement, port state control
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