BIS 50 Rule Calculator: The Supplier That Looked Clean Until We Mapped Ownership
If you are still doing 50% math in spreadsheets, you are one ownership update away from a bad day.
The supplier looked fine
It was a normal vendor onboarding. Good website, clean paperwork, solid pricing. They were not on the Entity List, not on the MEU List, and nothing in the initial screening popped.
So the team did what most teams do: they approved the supplier and moved on.
Two weeks later, somebody asked a simple question: “Who owns them?”
That question changed the whole story.
The problem is not the name, it is the ownership
Most screening programs are name-first. You type in an entity name, you check lists, you move on. But the BIS affiliates rule shifts the real risk into ownership and control. That means an entity can look clean by name, while being owned by someone you absolutely cannot touch.
And the kicker is this: the trigger is not only direct ownership. It can be indirect ownership through layers. It can also be aggregate ownership across multiple restricted parties. That is where spreadsheet math starts to break down.
How ownership hides in plain sight
Here is the pattern we see constantly:
- 1
Parent company is restricted (on the Entity List or similar).
- 2
Subsidiary is not listed by name.
- 3
Subsidiary becomes the “front door” for purchasing, sourcing, or contracting.
- 4
The business feels safe because the name checks out.
If your workflow stops at list matching leading to a "No Hit", you miss what matters.
So let’s make it painfully simple: The 30% plus 25% problem
The Scenario
Say you have a supplier called “Blue Harbor Components.”
Your screening returns clear. No list hits.
But ownership data shows:
- Owner A is a restricted party, 30%
- Owner B is a restricted party, 25%
- The rest is split across other owners
The Result
Aggregate restricted ownership.
even if neither owner is a majority by themselves, in aggregate the company is now inside the 50% scope.
Indirect ownership is where things get messy
Now add one more layer:
- 1Restricted Parent owns 60% of Holding Co
- 2Holding Co owns 50% of “Blue Harbor Components”
Calculation: 60% × 50% = 30% indirect ownership
That one number is easy. The real world rarely is. Real ownership chains look like 4 layers deep, multiple paths to the same parent, partial ownership at each step, and missing slices because nobody has the full picture.
Minority ownership can still be a red flag
Even when the 50% threshold is not met, significant minority ownership is not “no big deal.” It is a due diligence alarm bell.
Operational Rule: Treat 25% as a serious red flag that triggers extra review. This is not about panic, it is about not being blind.
How we built this into SecurePoint USA
Aggregate restricted ownership: Block or Escalate
Minority ownership: Red Flag, Due Diligence
Unknown ownership: Red Flag (Unknown is Risk)
And we do not stop at a number. We show the chain. If someone asks “why did we flag this,” you can answer with:
That is the difference between “we think” and “we can prove it.”
Use the BIS 50 Rule Calculator
If you want to sanity-check a case fast, use our tool. It lets you add owners and percentages, mark restricted parties, see aggregate ownership instantly, and flag minority red flags.
Open CalculatorWhat to do next: A workflow that holds up under pressure
Collect ownership data at onboarding
Ask for parent company, subsidiaries, and major shareholders.
Screen names and known owners
Do list screening, but do not stop there.
Compute ownership rollups
Direct, indirect, aggregate. Catch multi-owner math.
Escalate when thresholds hit
50% scope, 25% minority red flag, unknown ownership gaps.
Document the evidence
If you cannot prove it later, it did not happen.
Monitor for changes
Ownership changes, affiliates appear, risk flips overnight.
Related Resources
Frequently Asked Questions
What is the BIS 50% rule?
It is ownership-based scope: if restricted parties own 50% or more of an entity, including through affiliates and aggregate ownership, risk extends beyond the named list entry.
What does aggregate ownership mean?
Multiple restricted parties can collectively cross the threshold, even if none individually hits 50%.
Do indirect owners count?
Yes, ownership through layers counts, and you multiply percentages along the chain.
What is a minority ownership red flag?
A significant minority stake can indicate influence or control risk; it should trigger extra due diligence.
Should I rely on a calculator for legal decisions?
No, a calculator helps you triage and document math, it does not replace legal review.
A quick disclaimer: Educational content only, not legal advice.