OFAC Advisory Signals Stricter Approach to Maritime Sanctions Enforcement
The U.S. Treasury Department’s Office of Foreign Assets Control (OFAC) has issued an advisory that marks a decisive escalation in maritime sanctions enforcement, building on the foundation laid in 2020. The new guidance broadens the definition of Designated Persons and Entities (DSPs) and reinforces the U.S. government’s focus on actors and behaviors enabling sanctions evasion, particularly around Iranian oil exports.
The advisory identifies an increasingly sophisticated set of tactics used to evade sanctions, including the use of shadow fleets, falsified documentation, and front-organizations in third-party countries to mask ownership structures. These tactics are intended to obscure the origin and destination of sanctioned cargo.
A review of the regulatory highlights reveals a significant increase in stringency: the advisory now includes an expanded list of evasion tactics, highlighting falsified documentation, location and identity manipulation, and ship-to-ship (STS) transfers as core methods used to evade sanctions. Furthermore, multiple STSs trigger an in-depth investigation of all involved vessels, requiring research into multiple identification and location data points.
The advisory also highlights the use of location (GNSS) manipulation for the first time in a formal advisory. Additionally, it emphasizes the need to detect “zombie vessels” and identity manipulation, which involves using the IMO number of a vessel that has been scrapped and is no longer in operation.
To further strengthen enforcement, the advisory requires proof that vessels weren’t going dark: if a ship claims its Automatic Identification System (AIS) was off for legitimate reasons, it must provide documentation to support this claim. This move aims to prevent vessels from claiming they were not transmitting AIS data when, in fact, they were actively evading sanctions.
The advisory also introduces a strong focus on Iranian-linked oil tankers operating covertly, often poorly maintained, uninsured, and active in high-risk zones. It emphasizes the importance of registering vessels under jurisdictions with rigorous compliance standards, tightening oversight of flag registries.
The new OFAC advisory significantly widens the net of risks introduced in 2020, no longer limited to operators or vessel owners. Instead, it focuses on the full network of actors, enablers, and systems that allow sanctions evasion to scale. The advisory now includes insurers, financial institutions, brokers, and other commercial players who may unknowingly (or knowingly) support illicit behavior.
The move is seen as a decisive escalation in maritime sanctions enforcement, signaling a more stringent approach to combating sanctions evasion.
Original Article: 2025 OFAC Advisory: What Maritime Compliance Must Look Like Now — Windward