A tanker operator headquartered in one jurisdiction charters a vessel to a counterparty whose beneficial owner sits on the SDN List (OFAC's list of Specially Designated Nationals and blocked persons). The charterer is incorporated in a third country. Two separate sanctions regimes – one American, one British – may apply simultaneously, and they do not speak the same language. Which authority governs? What must the operator do, and within what time window? The answers determine whether the fixture survives, whether funds are blocked, and whether a criminal referral follows.
As of January 2026, maritime and shipping sanctions under OFAC and OFSI share broad aims but diverge sharply on ownership tests, jurisdictional reach, vessel-blocking mechanics, and reporting obligations. OFAC's rules rest on an extra-territorial model and a mechanical 50 percent ownership threshold; OFSI applies both an ownership and a control test, with a reporting window measured in days. For any cross-border vessel transaction touching both regimes, the stricter prohibition governs each element of the deal.
This analysis maps the key divergences across six dimensions – jurisdictional reach, the ownership and control test, vessel and cargo-blocking mechanics, the licence and authorisation routes, reporting and record-keeping obligations, and enforcement posture – and closes with the practical steps a cross-border business should take before it signs a charter, issues a bill of lading, or releases freight funds.
How does jurisdiction work under each regime?
OFAC's jurisdiction extends to all US persons wherever located, to transactions that clear through the US financial system, and to any conduct within the United States. That third limb – the dollar-clearing anchor – is what gives OFAC reach over non-US shipping firms. A Norwegian shipowner whose freight payment routes through a US correspondent bank is, for that moment, subject to OFAC's rules. A cargo insurer at Lloyd's that underwrites a US-flag vessel faces the same exposure. In our experience, the dollar-clearing nexus is the most frequently underestimated source of OFAC exposure for European and Asian shipping participants.
OFSI's jurisdiction is built differently. It covers persons operating in the United Kingdom, UK nationals anywhere in the world, and entities incorporated under the law of any part of the United Kingdom. A Bermuda-incorporated subsidiary of a UK parent is a UK person for this purpose. OFSI does not have a currency-anchor equivalent to OFAC's dollar-clearing rule, but sterling-denominated freight and demurrage payments will attract its attention where the payer or the bank is a UK person.
The divergence matters in practice. A cross-border shipping transaction can sit squarely within OFAC's reach while barely touching OFSI's, or vice versa. More often, both apply. The question is which prohibition is stricter on the specific element at issue – and under cross-border doctrine the stricter prohibition governs that element.
The ownership and control test: where the regimes part company most sharply
OFAC's 50 percent rule (the rule treating entities owned 50 percent or more by blocked persons as themselves blocked) is mechanical. Where blocked persons own an entity in the aggregate at or above that threshold – directly or through layers of intermediate holding companies – the entity is treated as blocked, regardless of who manages it or what the entity does. Intention and actual control are irrelevant to the threshold calculation. Aggregation across multiple blocked shareholders is required: two listed persons each owning 26 percent of the same shipowner reach the threshold together.
OFSI applies both an ownership test and a control test (the UK test for whether a non-listed entity is caught through a listed person's ability to direct or exercise significant influence over the entity's affairs). An entity can be caught under OFSI's rules even where no single listed person, and no combination of listed persons, owns 50 percent or more of the shares – provided a listed person holds a dominant position in, or has the ability to direct the entity's affairs. A vessel-owning company where a designated person holds a casting vote on the board, or where contractual rights give that person a veto on sale or chartering decisions, may be caught under the control test even where the equity is diffuse.
For shipping, this divergence has concrete implications. Beneficial ownership in the maritime sector is often deliberately layered – a flag-state registered operating company, a Marshall Islands holding company, a trust. OFAC analysis starts and ends with the 50 percent arithmetic. OFSI analysis requires an assessment of actual governance, side agreements, and management arrangements. A vessel that passes the OFAC ownership screen may still be caught by OFSI if a designated person exercises effective control over chartering decisions. Have you reviewed the constitutional documents and shareholder agreements, or only the registry data?
The position above covers the standard analysis. Your specific counterparty structure – the layers, the jurisdiction of incorporation, the nature of any side agreements – changes the outcome.
For a cross-regime assessment of a shipping counterparty's ownership and control structure, contact Calder & Vance at info@caldervance.com.
Vessel and cargo blocking: how each regime handles the asset
Under OFAC, a vessel owned or controlled by a blocked person is itself blocked property. US persons must not deal in it, provide services to it, or allow it to enter a US port without a licence. Cargo aboard a blocked vessel takes on the character of the vessel: even if the cargo owner is not itself designated, the cargo is effectively immobilised while on a blocked ship. Port service providers – bunkering, pilotage, stevedoring – face the same prohibition. A US classification society cannot survey a blocked vessel without an OFAC licence.
OFSI's approach to vessel blocking follows the same general principle – assets owned or controlled by a designated person are frozen – but the practical implementation in the maritime context differs. OFSI has published specific maritime guidance covering vessel management, insurance, and port-state obligations. The guidance addresses the position of UK-regulated P&I clubs and hull underwriters, whose cover obligations can intersect with the asset freeze where a designated person is the assured. In our cross-border practice, we regularly advise P&I clubs and their correspondents on the boundaries between ordinary marine insurance obligations and OFSI's freeze requirements.
Cargo owned by a non-designated person aboard a vessel that is itself blocked presents the sharpest practical problem. OFAC's position is that servicing the vessel – even to facilitate delivery of innocent cargo – requires a licence. OFSI's guidance acknowledges the operational tension and has addressed certain categories of humanitarian and safety-of-life-at-sea activity through its general-licence architecture. The two regimes do not map onto each other precisely here, and a cross-border operator must check both before taking any operational step.
How do the licensing routes compare?
OFAC issues two categories of authorisation: a general licence (a standing authorisation that permits a defined category of transactions without a separate application) and a specific licence (a case-by-case authorisation to conduct an otherwise prohibited transaction). In the maritime sector, OFAC has historically issued general licences covering certain safety-of-life-at-sea activities, ordinary maintenance of blocked vessels by non-US parties, and transactions necessary to wind down dealings with newly designated persons within a short defined window. Specific licences are available for transactions that fall outside general-licence coverage; OFAC evaluates them against its licensing policy for the relevant programme. Processing times for specific licences are not guaranteed and can extend to several months in practice.
OFSI issues a specific licence (the UK term for a case-by-case authorisation) and, separately, general licences that operate broadly in the same way as their OFAC counterparts. OFSI's licensing grounds are set by the relevant thematic sanctions regulations and include trade, humanitarian, legal services, and extraordinary situations. In the maritime context, OFSI has used its general-licence power to permit certain insurance and P&I activity that would otherwise be prohibited. The firm can assess whether an existing general licence covers a proposed transaction before a specific-licence application becomes necessary.
A critical divergence: where OFAC issues a general licence covering a category of transaction, that authorisation is available to any person who meets its terms – no prior approval is needed. OFSI's general licences operate similarly, but the terms and scope differ and cannot be assumed to mirror OFAC's. A US-law general licence does not authorise the same transaction under UK law, and vice versa. In a dual-exposure transaction, both sets of conditions must be satisfied independently. We advise on this mapping regularly; it is a common source of error in cross-border charter negotiations.
Reporting obligations and record-keeping: divergences in timing and scope
OFAC requires US persons to report the blocking or rejection of a transaction. A blocked transaction must be reported within 10 business days of the blocking, and an annual report of all blocked property must be filed thereafter. Rejected transactions – where a US person declines to process a payment because it would violate OFAC's rules, rather than blocking the funds – carry a separate reporting obligation within 10 business days. Records of blocked property must be kept for the duration of the blocking plus a further period; records of rejected transactions must be maintained for a standard period after the rejection. All figures here are from the verified registry and should be confirmed against current OFAC guidance before reliance.
OFSI's reporting regime operates on a different trigger. A UK person who knows or has reasonable cause to suspect that a person is a designated person, or that an asset is frozen, must report that suspicion to OFSI as soon as practicable. The obligation sits on the person who holds or handles the asset or the payment, not only on regulated firms. A shipowner who receives a freight payment and then identifies a concern about the beneficial ownership of the payer must report. The reporting is not conditional on a formal designation check returning a confirmed hit; reasonable suspicion is the threshold.
The record-keeping obligations also diverge. OFAC's record-keeping requirements for blocked property and rejected transactions run for defined periods set by the relevant programme regulations. OFSI's regime requires records sufficient to support the reporting obligation and any subsequent OFSI inquiry, but the specific retention periods differ by category of activity. For a cross-border transaction subject to both regimes, a compliance programme must satisfy the more demanding of the two obligations in each category.
If a transaction has already been flagged or a filing has been refused, an early review can preserve options that narrow with time.
For a confidential review of a potential breach or a reporting obligation, contact Calder & Vance at info@caldervance.com.
Enforcement posture: how OFAC and OFSI approach maritime violations
OFAC's civil enforcement programme operates on a strict-liability basis for civil violations: intent is not an element of liability, though it is a mitigating factor in penalty calculation. The civil monetary penalty base for a wilful or egregious violation can reach very large amounts; for non-egregious violations, penalties are calibrated against the statutory maximum and a range of aggravating and mitigating factors. A VSD (voluntary self-disclosure to a regulator) reduces the base penalty by a significant proportion under OFAC's published methodology. In the maritime sector, OFAC has demonstrated a sustained focus on shipping intermediaries – charterers, freight forwarders, ship managers, and flag-state registries – not only on vessel owners.
OFSI's civil enforcement regime is also strict-liability for financial penalties, and the penalty maximum was substantially raised by the relevant amendment to the Sanctions and Anti-Money Laundering Act ("SAMLA"). OFSI can impose a monetary penalty on a UK person for a breach of financial sanctions even where the person did not know and had no reasonable cause to suspect the breach, though knowledge and reasonable cause are factors in its published enforcement guidance. OFSI has also published its approach to the "reasonable steps" defence available in certain circumstances. In our experience, OFSI's enforcement posture in the maritime sector has intensified, with a focus on insurance, ship management, and correspondent relationships.
Criminal enforcement differs. OFAC refers criminal matters to the Department of Justice; criminal liability requires knowledge or wilful action. OFSI can refer criminal matters to the Crown Prosecution Service; the criminal offence under SAMLA also requires knowledge or reasonable cause to suspect. The practical implication: a compliance failure that is purely inadvertent may remain in the civil sphere, but a pattern of conduct that disregards red flags can cross the criminal threshold under either regime. A VSD, filed promptly and with a well-constructed remediation narrative, is the most effective tool available for keeping a civil matter civil. We have guided clients through this process under both regimes.
A scenario: the dual-exposed tanker fixture
Consider a cross-border fact pattern that illustrates the divergences described above. A European ship manager receives a charter enquiry for a products tanker. The charterer is a commodity trader incorporated in a jurisdiction outside the US and UK. The trader's ultimate beneficial owner holds a minority stake – under 50 percent – in the trader but holds a contractual right to approve all vessels chartered. A routine OFAC screen returns no hit on the trader. A deeper review identifies the beneficial owner as a person designated under a non-US regime.
Under OFAC's 50 percent rule, the trader is not blocked: the ownership arithmetic does not reach the threshold, and the designated person is not on the SDN List. The ship manager, if a US person or using US correspondent banking, faces no OFAC prohibition on this analysis alone. But the analysis does not end there. OFSI's control test asks whether a designated person can direct or exercise significant influence over the trader's affairs. The contractual approval right over vessel selection is precisely the kind of governance right that OFSI examines. If the beneficial owner is also designated under the UK regime, the trader may be caught by OFSI's control limb even though it clears OFAC's ownership screen.
In a recent matter, a ship management business in this position engaged us to map the full ownership and control chain across both regimes before committing to the fixture. We assessed the ownership arithmetic, reviewed the constitutional documents and the side agreement, and identified the OFSI control risk. The matter was restructured to address the UK exposure before signing. No licence application was required because the structural analysis resolved the issue at the due-diligence stage. This is the value of cross-regime diligence: issues identified before signature are resolved at low cost; issues identified after an enforcement notice are resolved at very high cost.
Common myths and risk flags in cross-border maritime sanctions
A persistent myth in the shipping industry is that flag-state registration confers protection from sanctions exposure. It does not. OFAC's rules apply to US persons and dollar-clearing transactions regardless of where a vessel is flagged. OFSI's rules apply to UK persons regardless of the vessel's flag. A vessel flying a non-sanctioned flag that is owned by a blocked person is still blocked property. Flag state provides administrative convenience; it provides no sanctions shield.
A related misconception is that P&I cover automatically falls away when a vessel is sanctioned, relieving the club of the need to analyse its own obligations. In practice, P&I clubs incorporated or managed in the UK are UK persons subject to OFSI's rules, and their obligations to an assured who is a designated person – or whose vessel is blocked – require careful analysis under OFSI's maritime guidance. The same applies to UK-connected hull and machinery underwriters. We regularly advise on this intersection.
The risk flags that most frequently arise in cross-border maritime due diligence include: ship-to-ship transfers in high-risk areas; AIS transponder gaps or manipulation; mismatched cargo descriptions against bill-of-lading data; frequent flag or ownership changes in a short window; and freight payment routes that pass through jurisdictions with weak sanctions controls. Any one of these flags warrants a deeper investigation of the vessel's recent call history and beneficial ownership before the fixture proceeds. None of these flags is conclusive evidence of a sanctions breach, but each raises the probability that a further inquiry is needed – and the cost of not conducting it.
Related practices and further analysis
Related practices
- Correspondent banking and de-risking – OFAC sanctions exposure for banks and payment firms handling cross-border freight finance
- OFSI vs EU: maritime and shipping sanctions divergences – the UK and EU positions compared across the same six dimensions
- Payment and escrow structuring: BIS EAR vs EU – dual-use and export-control considerations for cross-border payment structures