A commodities trader in Singapore is close to signing a supply agreement with a distributor registered in a third jurisdiction. The distributor has three shareholders. One of them does not appear on any sanctions list. But that shareholder is itself owned by an entity whose parent has been designated under a major OFAC programme. Does the prohibition extend down the chain? The trader's legal team needs an answer before the wire transfer goes out.
Under OFAC's 50 percent rule (the rule that treats any entity owned 50 percent or more in the aggregate by blocked persons as itself blocked, regardless of whether it appears on any published list), the analysis is mechanical rather than discretionary. As of July 2026, a business conducting ownership and control assessments OFAC requires a structured, multi-layer inquiry: identify every blocked person with a direct or indirect stake, aggregate those stakes at each tier, and apply the threshold. Stopping at the first ownership layer is the most reliable way to reach the wrong answer.
This guide walks through the assessment in seven stages, addresses where OFSI and EU tests diverge from OFAC's approach, and flags the points where involvement of a sanctions lawyer is not optional.
Step 1 – Understand what you are looking for before you start
The 50 percent rule is the operative legal standard under IEEPA-based OFAC sanctions programmes, and the starting question is whether any person who is blocked under the applicable programme owns, directly or indirectly, fifty percent or more of the entity in question, in the aggregate with any other blocked persons.
That sentence contains three working parts that each require attention. First, "blocked under the applicable programme" – a person blocked under one OFAC programme is not necessarily blocked under another. Different programmes have different lists and different definitions. The entity under review and the counterparty relationship must both be traced to a specific programme, not to "OFAC" as an undifferentiated concept.
Second, "directly or indirectly" – the rule reaches through intermediate holding companies, trusts, and nominee structures. An intermediate entity that is not itself listed is still a link in the chain. Its presence does not interrupt the analysis.
Third, "in the aggregate" – multiple blocked persons, each with a minority stake, can together reach the threshold. A ten-percent holding by blocked person A and a forty-five-percent holding by blocked person B gives a combined position of fifty-five percent. The entity is blocked. Neither holder alone would have triggered the rule.
Before beginning, confirm which programme or programmes are relevant to the counterparty, the goods or services, and the transaction. That scoping step determines which list or lists you screen against, and which OFAC guidance applies.
Step 2 – Gather the ownership documentation
Reliable data on ownership structure is the foundation of the entire assessment, and weak documentation is where most ownership errors originate in our experience.
The practical document set required at this stage typically includes: a corporate registry extract or equivalent official filing showing the current legal ownership; a copy of the shareholder register or capitalization table, confirmed as current; constitutional documents if ownership thresholds are set by class of shares rather than headcount; any disclosed trust arrangements that affect beneficial ownership; and a written representation from the counterparty confirming the completeness of the information provided.
Where the counterparty is domiciled in a jurisdiction without a publicly accessible corporate registry, or where registry data has not been updated recently, there is an additional burden to seek direct confirmation. A counterparty that is reluctant to provide current ownership documentation is itself a risk signal.
The documentation must reflect the position as of the date of the transaction, not the date of the last periodic review. Ownership structures change. A shareholder that held a compliant stake twelve months ago may have transferred or expanded that stake. Sanctions designations are also ongoing: a previously clean shareholder may have been added to a list after your last check.
Step 3 – Screen every ownership layer, not just the direct shareholders
The mechanical core of the assessment is a layer-by-layer review from the counterparty upward through every intermediate entity to the ultimate beneficial owners, cross-referencing each name at each tier against the relevant OFAC consolidated list or programme-specific list.
In practice this means building an ownership map. Start at the counterparty itself. Identify every direct shareholder and their stake. Then treat each direct shareholder as the next subject of review: who owns that shareholder? Work upward until you reach a natural person, a state entity, or a publicly listed company with no further traceable private ownership, at each tier recording the percentage held.
The screening at each tier must cover: the legal name of the entity or person; known aliases, alternative transliterations, and former names; the jurisdiction of incorporation or residence; and any identification numbers that appear in the available documentation.
Have you checked whether your screening tool is configured to identify entities blocked by operation of the 50 percent rule, and not only those that appear by name on a published list? A tool that performs only name-match screening against the SDN List misses the entire category of unlisted-but-blocked entities. The gap can be significant.
Fuzzy-matching logic in screening tools varies. A match score that is set too high will miss genuine hits; one set too low will generate excessive false positives that consume compliance resource without improving accuracy. Both calibration failures carry risk.
Step 4 – Aggregate blocked-person stakes at each ownership tier
Once the layer-by-layer map is complete and the list screening has been run, the aggregation calculation begins. At every tier in the ownership chain, add together the stakes held by all persons that have been identified as blocked. If the aggregate at any tier equals or exceeds 50 percent, the entity at that tier is blocked, and the blocking cascades downward to any entities in which that tier holds a majority.
An example in outline: a target entity has four shareholders. Shareholder A holds twenty percent and is not blocked. Shareholder B holds twenty percent and is blocked under the applicable programme. Shareholder C holds twenty percent and is not blocked. Shareholder D holds forty percent and is also blocked. The aggregate blocked stake is sixty percent. The target entity is blocked by operation of the 50 percent rule, even though neither blocked shareholder holds a majority individually.
The aggregation must be re-run at each intermediate tier. If the target's parent company has a different ownership composition, you run the same calculation there as well. Blocking is not inherited simply because a parent is blocked; each tier must be assessed on its own composition. But a blocked parent that holds fifty percent or more of a subsidiary blocks that subsidiary directly, because the blocked parent's interest in the subsidiary is the relevant figure.
In our practice, we have seen aggregation errors appear most often in three situations: group structures with multiple minority investors, including private equity or sovereign wealth fund co-investors; structures where the same ultimate beneficial owner holds stakes through multiple intermediate entities that each fall below the threshold; and structures where a trust or foundation holds the relevant stake and the beneficiaries – rather than the trustee – are the relevant persons for sanctions purposes.
Step 5 – Address the control question and the divergence with OFSI and EU rules
Under OFAC's standard, the 50 percent rule is the operative threshold. OFAC does not, for purposes of this rule, impose a parallel "control" test that would block an entity where a blocked person has effective operational control but holds less than fifty percent of the ownership. That is a meaningful limitation of the OFAC test, and it matters for cross-border transactions.
OFSI and the EU apply a different standard. Both regimes impose an ownership and control test, which means an entity that is owned or controlled by a listed person may be caught. "Control" in those regimes can extend to situations where a listed person has the ability to direct the decisions of the entity – through contractual rights, board composition, veto rights, or other mechanisms – even if their direct ownership stake is below fifty percent. This is the single most important point of divergence between OFAC and its counterparts in London and Brussels.
For a business operating across multiple jurisdictions simultaneously, the practical implication is this: an entity that is not blocked under OFAC's ownership test may nonetheless be off-limits under OFSI or EU rules, because a listed person holds a control position without a majority stake. Compliance counsel conducting a cross-regime review must run both analyses. Applying only the OFAC standard to a transaction that also has a UK or EU nexus may leave the business exposed.
Switzerland, Canada, and Australia each maintain their own ownership and control tests, and while they broadly follow either the OFAC or the EU model, the details differ. A global or multi-regional transaction should be assessed under each applicable country regime, not assumed to mirror OFAC's position.
Where a transaction has a US nexus – payment in US dollars, US-origin goods, a US counterparty, or US persons involved in any role – OFAC's analysis is primary. Where the nexus is primarily UK or EU, OFSI's and the EU Council's tests govern, and the control question cannot be bypassed by demonstrating that ownership sits below fifty percent.
Step 6 – Apply the result to the transaction and identify the available options
Once the assessment is complete, there are three possible outcomes, and each has a different operational consequence.
Outcome one: no blocked persons are identified in the ownership chain at any tier, the aggregation test is not triggered, and the counterparty is not blocked. The transaction may proceed, subject to any other applicable sanctions prohibitions – country-based, sectoral, or transactional – and subject to any export-control requirements that are separate from the ownership analysis. Record the assessment and its basis.
Outcome two: the assessment identifies blocked-person ownership below the fifty percent threshold, with no control issue under the applicable regime. Under OFAC's rules, the entity is not blocked by operation of the 50 percent rule. However, transacting with a company in which a blocked person holds any material stake is itself a risk indicator. Enhanced monitoring, additional due diligence, and a clear record of why the transaction was assessed as permissible are all warranted. If the transaction also has a UK or EU nexus, the control analysis for those regimes must still be completed.
Outcome three: the threshold is met or exceeded, or a control relationship is established under the applicable regime. The entity is blocked. The transaction cannot proceed as structured. The available routes from this position are: restructure the transaction to eliminate the prohibited nexus; seek an OFAC specific licence authorising the particular activity; or not proceed.
A specific licence (a case-by-case authorisation from OFAC for a transaction that would otherwise be prohibited) is a real option in some circumstances, but it is not a default workaround and it carries no guarantee. Processing times vary and can be substantial. The application must demonstrate both the grounds for authorisation and the absence of circumvention purpose. Engaging compliance counsel at this stage is strongly advisable.
If a transaction has already been flagged – by your own screening, by a correspondent bank, or by a regulator – an early review can preserve options that narrow with time. For a confidential assessment of a specific transaction, contact Calder & Vance at info@caldervance.com.
Step 7 – Document the assessment and establish a review cycle
An ownership and control assessment is not a one-time exercise. Ownership structures change, new designations are issued, and counterparty information provided at onboarding may become stale. The assessment must be documented at the time it is conducted, and there must be a defined trigger or schedule for re-assessment.
Documentation should record: the date of the assessment; the version of the relevant list or lists screened; the ownership information relied upon and its source; the aggregation calculation; the outcome; and who conducted and reviewed the analysis. This record serves two purposes: it demonstrates reasonable care if a breach investigation later arises, and it provides the baseline for re-assessment.
Re-assessment triggers include: any change in the counterparty's disclosed ownership; any new OFAC designation that affects a name in the ownership chain; any material change in the transaction terms; and a periodic review cycle, the frequency of which should reflect the risk profile of the counterparty relationship. Higher-risk counterparties in sectors or jurisdictions with elevated sanctions exposure should be reviewed more frequently than standard commercial relationships.
Record-keeping requirements under the applicable US regime specify a defined retention period. Verify the current requirement before establishing your archive policy, and apply the longer retention period if multiple regimes with different rules apply to the same transaction file.
In our experience advising compliance teams, the documentation step is the one most frequently treated as an administrative afterthought. It is not. In the event of an enforcement inquiry, the quality of contemporaneous documentation is often the deciding factor between a matter resolved at the voluntary self-disclosure stage and one that escalates.
Common mistakes and when to involve a sanctions lawyer
Across ownership and control assessments, a consistent set of errors appears in practice. Addressing them directly is more useful than listing them abstractly.
Stopping at the first layer. The 50 percent rule applies to indirect ownership. An assessment that screens only the direct shareholders of the target entity and stops there does not satisfy the rule. Intermediate holding companies, nominee shareholders, and trust arrangements are each a layer that must be examined.
Confusing "not listed" with "not blocked." An entity that does not appear by name on the SDN List or any other published list may nonetheless be blocked under the 50 percent rule. These are different things. A compliance programme that treats a clean name-match result as conclusive of permissibility will miss a category of prohibited counterparties.
Applying only the OFAC standard to a multi-regime transaction. A business with a UK bank account, EU subsidiaries, or European personnel involved in a transaction must also run the OFSI and EU ownership-and-control tests. As noted above, those tests include a control limb that OFAC's does not. Missing the cross-regime dimension is a structural error, not a technical one.
Treating a dated assessment as current. Ownership structures are not static. Neither are sanctions lists. An assessment conducted at onboarding may not reflect the position at the time of execution, particularly where significant time has elapsed or where the relevant sanctions programme has seen new designations.
When should a sanctions lawyer be involved? At a minimum: where any tier of the ownership chain returns a possible match that the screening tool cannot resolve; where ownership is held through a trust, foundation, or nominee arrangement; where the transaction has a multi-regime dimension; where the aggregate blocked-person stake is anywhere near the fifty percent threshold; and where the counterparty is unwilling or unable to provide complete ownership documentation. In those situations, proceeding without specialist advice carries disproportionate risk.
We regularly advise businesses at the point where a screening result has created uncertainty and a decision is needed. The question is rarely abstract – it is usually: can this specific transaction proceed, on these terms, on this timeline? That is the question we address.
A practical scenario
In a recent matter, a financial services business was evaluating a correspondent banking relationship with a financial institution in a third jurisdiction. Screening of the institution's direct shareholders returned no matches. However, a review of the second-tier ownership revealed that two indirect shareholders – each holding approximately twenty-five percent of a first-tier holding company that itself held sixty percent of the institution – were both subject to OFAC designations under the applicable programme. Their aggregate indirect stake in the institution, when traced through the holding company, exceeded fifty percent. The institution was blocked by operation of the 50 percent rule. The correspondent relationship was not established. The business avoided a potential enforcement exposure that would not have been identified by a first-layer screen alone.
The matter also had a UK nexus. We assessed the position under OFSI's rules, which include a control test. The same conclusion was reached under both regimes, though the legal basis differed.
Related practices
- Sanctions compliance audit and testing (Australia) – review and test your compliance programme against the Australian autonomous sanctions regime
- Ownership and control assessments under OFAC – guide 3 – advanced topics: trusts, nominees, and multi-regime aggregation
- Ownership and control assessments under OFAC – guide 4 – sector-specific applications and enhanced due diligence procedures