Customs Prior Disclosure Timing: What CBP Knowledge Really Means

Key Points

• A prior disclosure filed under 19 U.S.C. 1592(c)(4) eliminates penalty exposure entirely, but only if it arrives before CBP has commenced a formal investigation or has otherwise obtained knowledge of the violation.
• CBP treats an investigation as commenced when a specific, targeted inquiry into a potential violation has begun, not merely when a routine query or informational port contact has occurred.
• A phone call or email from a port asking general questions does not automatically constitute CBP knowledge, but a formal audit notice, a CF-28 or CF-29 focused on the same issue, or a referral to the Fines, Penalties, and Forfeitures (FP&F) office almost certainly does.
• If the tender window has already closed, a prior disclosure still carries significant mitigation value under CBP's penalty guidelines, but it does not eliminate liability.
• Filing speed is the single most consequential variable: hours and days matter, because the factual record of when CBP first learned of a potential violation is often reconstructed after the fact.

On this page

1. What prior disclosure is and what it does under 19 U.S.C. 1592
2. The statutory tender window: before or without knowledge
3. What counts as CBP knowledge: commenced investigation defined
4. Port contacts that do and do not trigger the knowledge threshold
5. What happens when the window has already closed
6. What importers should do
7. Key references

A prior disclosure filed at exactly the right moment eliminates all penalty exposure for a customs violation under 19 U.S.C. 1592. Filed one day too late, the same disclosure becomes a mitigation factor rather than a complete shield. The entire analysis turns on a single question: did CBP already have knowledge of the violation, or had it already commenced a formal investigation, before the importer tendered the disclosure?

The links in this article go to the primary documents: the statutes, CBP guidance pages, and official regulatory sources themselves. Read the source.

What Prior Disclosure Is and What It Does Under 19 U.S.C. 1592

19 U.S.C. 1592 prohibits material false statements, omissions, and acts in connection with the entry of merchandise into the United States. Violations are graded by culpability: fraud, gross negligence, and negligence each carry different penalty ceilings, expressed as multiples of the unpaid duties or of the dutiable value of the merchandise.

Section 1592(c)(4) creates a specific incentive for self-correction. When an importer or its broker makes a timely prior disclosure, the maximum penalty that CBP may assess is reduced to the interest on the unpaid duties. In practice, CBP's own penalty mitigation guidelines treat a valid prior disclosure as eliminating the penalty entirely, with only the unpaid duties and interest remaining due. That is a dramatic outcome compared to a fraud penalty that can reach the full domestic value of the merchandise.

To secure that outcome, the statute requires that the disclosure be made before CBP has commenced a formal investigation of the alleged violation, or before CBP has otherwise obtained knowledge of it. Both prongs of that test require careful analysis.

The Statutory Tender Window: Before or Without Knowledge

The phrase "before or without" in the statute is disjunctive. Either condition independently satisfies the timing requirement:

• Before commencement: The disclosure arrives before CBP has formally begun an investigation targeting the specific violation at issue.
• Without knowledge: Even if CBP has not yet formally commenced an investigation, if the agency has independently obtained knowledge of the same violation through other means, the window is also closed.

Both conditions are evaluated at the moment of tender, meaning the date and time the written prior disclosure is actually submitted to the appropriate CBP office. This is not the date the importer decided to file, not the date an attorney was retained, and not the date a correction was identified internally. The moment of tender is the operative fact.

CBP has issued guidance clarifying how it interprets these two prongs in practice. The agency's prior disclosure program guidance describes the procedural requirements, including where to file, what the disclosure must contain, and how CBP calculates the duty owed. Importers and brokers should read that page before filing anything.

What Counts as CBP Knowledge: Commenced Investigation Defined

CBP treats an investigation as commenced when agency personnel have initiated a specific, targeted inquiry directed at a particular importer or entry for a particular potential violation. The inquiry must be more than generalized surveillance, trade-data analysis, or an unrelated audit.

Factors CBP considers

• Whether a specific referral to the FP&F office has been made regarding the importer and the class of violations at issue.
• Whether a formal audit notice, such as a Focused Assessment notification from the Office of Trade, has been issued covering the same subject matter.
• Whether a CF-28 (Request for Information) or CF-29 (Notice of Action) has been sent that is directed at the same entries or the same type of alleged violation.
• Whether a Special Agent from Homeland Security Investigations has made contact regarding the same conduct.

The knowledge prong

Even without a formal investigation, the window closes if CBP has obtained independent knowledge of the violation. Examples include a tip from a third party relayed through a port, a parallel investigation of a supplier that reveals the importer's conduct, or interception of a shipment that surfaces the underlying misclassification or undervaluation. If CBP knows, the window is closed regardless of whether anyone has formally announced an investigation.

Because CBP's internal records are not always available to the importer in real time, any ambiguity about what CBP may already know should be resolved in favor of filing immediately.

Port Contacts That Do and Do Not Trigger the Knowledge Threshold

This is where the analysis becomes genuinely difficult. Not every communication from CBP signals that the tender window has closed.

Contacts that generally do not close the window

• A routine courtesy call from a port trade specialist asking general questions about an importer's product line, with no reference to specific entries or specific potential violations.
• A request for a meeting to discuss compliance topics generally, not focused on specific entries.
• A CBP binding ruling request follow-up that is administrative in nature.

Contacts that likely do close the window

• A CF-28 or CF-29 directed at the same entries or the same classification or valuation issue the importer is considering disclosing.
• A formal Focused Assessment notification from the Office of Trade covering the period of the potential violations.
• Any direct communication from an FP&F office referencing specific entries or a specific potential penalty.
• A visit from a special agent or a request for records that is clearly investigative in character.

The difficulty is that some contacts fall in a gray zone. A CF-28 on classification for one product does not automatically close the window for a separate valuation disclosure. But if the CF-28 touches the same entries, the same HTS heading, or the same course of conduct, a court or CBP adjudicator could find that CBP had sufficient knowledge to close the window on the related issue as well.

If your company is working to identify duty underpayments proactively, the guide How Do I Find Duty Underpayments Before CBP Does? outlines a systematic approach to self-auditing before any CBP contact occurs, which is the cleanest factual posture for a prior disclosure.

What Happens When the Window Has Already Closed

A prior disclosure filed after CBP has commenced an investigation or obtained knowledge does not eliminate penalty liability. However, it remains a significant mitigating factor under CBP's penalty mitigation guidelines. CBP considers the fact that an importer voluntarily came forward, cooperated, and tendered unpaid duties when determining how far below the statutory maximum to set the penalty amount.

The practical difference between a timely and an untimely disclosure can still be substantial in terms of negotiated outcomes. An importer who makes a complete and accurate disclosure after the window closes, tenders all unpaid duties promptly, and cooperates fully is in a far better position than one who waits for CBP to issue a penalty notice before engaging.

When a penalty notice does arrive, it typically comes on a CBP Form 5955A, which initiates the formal penalty process and triggers response deadlines. Understanding that form and its timelines is a separate but related compliance task.

It is also worth noting that the prior disclosure framework under 1592(c)(4) applies specifically to penalties for material false statements and related violations. It does not eliminate unpaid duties, interest, or other consequences. And for entries that have already liquidated incorrectly, a protest or other correction mechanism may also be needed alongside the prior disclosure.

What Importers Should Do

• File immediately upon identifying a potential violation. Do not wait to fully quantify every dollar of unpaid duties before tendering the disclosure. CBP's guidelines allow for an initial disclosure followed by a supplemental tender of duties once the calculation is complete. Speed in filing the initial disclosure protects the tender window; the duty calculation can follow.
• Document every CBP contact with date, time, content, and the identity of the CBP officer involved. If the timing of the window is ever disputed, this contemporaneous record is your evidence that the disclosure preceded CBP knowledge.
• Analyze every piece of CBP correspondence against the specific violation you are considering disclosing. A CF-28 or audit notice on a different issue does not automatically close the window for the subject matter of your disclosure, but the analysis must be done entry by entry and issue by issue.
• Conduct proactive internal audits on a regular schedule so that potential violations are identified before any CBP contact occurs. The earlier in the compliance cycle a problem is found, the more clearly the tender window remains open.

Key References

• 19 U.S.C. 1592: The governing statute for customs fraud and material false statement penalties, including the prior disclosure provision at subsection (c)(4).
• CBP Prior Disclosure Program (cbp.gov): CBP's official guidance on where to file, required content, and how the program works.
• 19 C.F.R. Part 171 (ecfr.gov): CBP regulations governing penalties and the petition process, including mitigation guidelines.
• CBP Form CF-28 (cbp.gov): CBP's Request for Information form, a common early-stage contact that may or may not signal commencement of a formal investigation depending on its focus.
• Federal Register (federalregister.gov): Source for any Federal Register notices related to CBP penalty policy updates.