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PSC vs 19 USC 1520(d) vs 19 CFR 174 Protest: Which Recovery Mechanism When

Four post-entry correction mechanisms are available to US importers, each with a different window, standard of review, and set of grounds. This decision tree walks through when to use Post Summary Correction, 19 USC 1520(d) FTA refund claim, 19 USC 1514 protest, and 19 USC 1520(c)(1) clerical-error reliquidation, with the sequencing rules CBP enforces.

Updated 2026-08-227 min read

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PSC vs 19 USC 1520(d) vs 19 CFR 174 Protest: Which Recovery Mechanism When

Four post-entry correction mechanisms are available to US importers, each with a different window, standard of review, and set of grounds. Picking the right one is a two-variable problem: what is the correction about (classification, valuation, FTA claim, clerical error), and where in the entry lifecycle is the entry (pre-liquidation, post-liquidation but within protest window, past protest window).

This decision tree walks through PSC, 1520(d), 19 USC 1514 protest, and 19 USC 1520(c)(1) reliquidation, with the sequencing rules CBP enforces. The findings queue surfaces recoverable items with the recommended mechanism attached, and the tasks queue drafts the filing.

The four mechanisms at a glance

Mechanism	Window	Grounds	Standard
PSC (19 CFR 141.114)	Pre-liquidation, 314 days from entry	Any correction	Amendment, no formal review
1520(d) (19 USC 1520(d))	1 year from date of importation	Missed FTA preferential claim only	Written declaration + certificate
Protest (19 USC 1514)	180 days from liquidation	Any protestable decision	Formal review by Port Director
1520(c)(1) reliquidation (19 USC 1520(c)(1))	1 year from liquidation	Clerical error, mistake of fact, other inadvertence	Tight standard, factual only

PSC: pre-liquidation correction

PSC under 19 CFR 141.114 is an amendment to a live entry summary. Available before the entry liquidates and within 314 days of entry, whichever comes first. Grounds are wide open: classification correction, value adjustment, missed FTA claim, missed exclusion, wrong Chapter 99 stack, MPF or HMF fix, quantity correction.

Filing is via ACE ABI. The amended 7501 supersedes the original and liquidates on the amended terms. Cash deposit adjustments happen automatically at liquidation.

PSC is the fastest and cheapest mechanism because there is no formal CBP review layer. If the amendment is facially reasonable, it stands. CBP can reject a PSC (usually for missing supporting documentation) but rejection resets the clock rather than closing the correction path; the importer can address the rejection and refile within the remaining window.

Use PSC when: entry is unliquidated, within 314 days of entry, and the correction is straightforward.

1520(d): missed FTA preferential claim

19 USC 1520(d) is the post-importation refund path for missed FTA preferences. Window is 1 year from date of importation, which is a shorter clock than PSC or protest for early-liquidating entries.

Filing package requires the FTA certification of origin from the producer or exporter, a written declaration from the importer of record that the goods qualified for preferential treatment at time of importation, and calculation of the refund amount per entry line.

1520(d) applies to: USMCA (19 CFR 181.31), KORUS (19 CFR 10.1004), US-Chile, US-Colombia, US-Panama, US-Peru, DR-CAFTA, US-Singapore, US-Australia, US-Morocco, US-Bahrain, US-Oman. GSP has its own refund mechanism at 19 USC 1520(a).

Use 1520(d) when: the missed claim is FTA preferential treatment specifically, and the entry is either past the PSC window or already liquidated but within 1 year of importation.

See missed FTA preferences: your 1-year recovery window for the full filing structure.

19 USC 1514 protest: post-liquidation formal challenge

Protest under 19 USC 1514 (regulations at 19 CFR 174) is a formal challenge to a CBP liquidation decision. Window is 180 days from date of liquidation.

Protestable decisions include:

The appraised value of the merchandise.
The classification and rate of duty applied.
The exclusion of merchandise from entry.
The liquidation or reliquidation of an entry.
Any decision of a Port Director.

Protest is the mechanism after PSC becomes unavailable (entry liquidated) and before the 1-year 1520(c)(1) clerical-error clock starts to matter.

Filing is on CBP Form 19 (or via ACE). The protest goes to the Port Director at the port of entry for initial review, and can be escalated to the CEE for higher-level review or ultimately to the Court of International Trade under 28 USC 1581(a) if denied.

For scope-related protests on AD/CVD entries, the protest is often suspended pending the current Commerce administrative review's final results.

Use protest when: entry is liquidated and within 180 days, and the correction is not eligible for 1520(d) (i.e., not a missed FTA claim).

19 USC 1520(c)(1) reliquidation: clerical error

The standard is tight. Case law under 1520(c)(1) has consistently held:

Typographical errors on the 7501: clerical error, qualifies.
Wrong exporter certification number transcribed from source document: clerical error, qualifies.
Broker misunderstood the scope of a Section 301 exclusion: legal error, does not qualify.
Importer disagrees with the classification CBP applied: legal error, protest is the path (if within window) rather than 1520(c)(1).

Use 1520(c)(1) when: entry is past the protest window (more than 180 days from liquidation), and the error is a pure factual mistake, not a judgment call.

The decision tree

Follow this flow for any post-entry correction:

Step 1: Is the correction a missed FTA preferential claim?

Yes and within 1 year of importation → 1520(d) is available regardless of liquidation status. Prefer PSC if pre-liquidation and within 314 days for speed.
No → continue.

Step 2: Is the entry pre-liquidation and within 314 days of entry?

Yes → PSC.
No → continue.

Step 3: Is the entry within 180 days of liquidation?

Yes → protest under 19 USC 1514.
No → continue.

Step 4: Is the entry within 1 year of liquidation and is the error a pure factual mistake?

Yes → 1520(c)(1) reliquidation.
No → correction window is closed. Consider drawback if the underlying goods were subsequently exported; otherwise, the overpayment is unrecoverable.

Sequencing rules CBP enforces

CBP will reject duplicative filings on the same issue. The rules:

A PSC and a 1520(d) on the same issue cannot both be pending. File PSC first if within window; if the PSC is rejected on procedural grounds, then file 1520(d) if still within the 1-year importation window.
A protest and a 1520(d) on the same issue cannot both be pending. Protest is broader; 1520(d) is narrower to FTA claims. If the missed FTA is the only issue, 1520(d) alone. If there are additional issues, protest covering all.
A protest and a 1520(c)(1) on the same issue cannot both be pending, and 1520(c)(1) does not extend or restart the protest window.

Timeline example: a USMCA-qualifying Mexican entry

Suppose an entry from Mexico with USMCA-qualifying goods was filed at Column 1 general rates. Timeline:

Day 0: Date of importation and entry.
Day 15: Entry summary filed at Column 1 general rates.
Day 45: Broker notices the miss.
PSC window: Days 15 through 314 (before liquidation).
Liquidation: typically day 315 for a routine entry.
Protest window: 180 days from liquidation, days 315 through 495.
1520(d) window: 365 days from importation, days 0 through 365.
1520(c)(1) window: 1 year from liquidation, days 315 through 680.

At day 45, the correction is inside the PSC window and inside the 1520(d) window. PSC is faster and covers the correction fully. File PSC.

At day 200, the correction is still inside the PSC window and inside the 1520(d) window. Still PSC.

At day 320, the entry has liquidated. PSC is unavailable. 1520(d) is still open (day 320 is inside the 365-day window from importation). Protest is also open (day 320 is 5 days into the 180-day post-liquidation window). Because 1520(d) is the narrower mechanism designed for exactly this situation, file 1520(d).

At day 400, 1520(d) has closed. Protest is still open (day 400 is 85 days into the 180-day post-liquidation window). File protest.

At day 500, protest has closed. 1520(c)(1) is available only if the miss is a clerical error, which "broker did not know USMCA applied" is not. Correction window is closed.

Detection: which mechanism the LandedFees engine recommends

The findings queue surfaces recoverable items with the recommended mechanism attached, computed from the entry lifecycle position and the type of correction. The tasks queue drafts the filing package with the correct form (PSC amendment, 1520(d) refund claim, CBP Form 19 protest, or 1520(c)(1) reliquidation request) and the required supporting documentation checklist.

For portfolio-scale corrections, running the leakage scan on a full 12-month lookback and prioritizing by deadline urgency (1520(d) 1-year deadlines first, then PSC 314-day deadlines, then protest 180-day post-liquidation deadlines) captures the largest recoverable dollars before any deadlines close.

Run the recovery workflow at landedfees.com/audit.

Citations

19 CFR 141.114 PSC: https://www.ecfr.gov/current/title-19/chapter-I/part-141/subpart-B/section-141.114
19 USC 1520: https://www.law.cornell.edu/uscode/text/19/1520
19 USC 1514: https://www.law.cornell.edu/uscode/text/19/1514
19 CFR Part 174 protest: https://www.ecfr.gov/current/title-19/chapter-I/part-174
19 CFR 181.31 USMCA post-importation claims: https://www.ecfr.gov/current/title-19/chapter-I/part-181
28 USC 1581 Court of International Trade jurisdiction: https://www.law.cornell.edu/uscode/text/28/1581

Frequently asked questions

What is Post Summary Correction?

Post Summary Correction under 19 CFR 141.114 is an amendment to an already-filed entry summary that can be filed before liquidation and within 314 days of entry. PSC is the fastest and cheapest correction mechanism because it operates on the live entry and does not require CBP formal review; the amended 7501 supersedes the original and liquidates on its terms.

What is a 19 USC 1520(d) claim?

A 19 USC 1520(d) claim is a post-importation refund claim for missed free trade agreement preferential treatment. The claim must be filed within 1 year of the date of importation and applies only to FTA-related refunds (USMCA, KORUS, US-Chile, US-Colombia, US-Panama, US-Peru, DR-CAFTA, US-Singapore, US-Australia, US-Morocco, US-Bahrain, US-Oman).

What is a 19 USC 1514 protest?

A 19 USC 1514 protest is a formal challenge to a CBP liquidation decision, filed after liquidation and within 180 days. Protest grounds include classification, valuation, rate of duty, and any decision of a Port Director. Protest is the primary mechanism to recover overpayments discovered after liquidation.

When does 19 USC 1520(c)(1) apply?

19 USC 1520(c)(1) authorizes CBP to reliquidate an entry to correct a clerical error, mistake of fact, or other inadvertence not amounting to an error in the construction of a law. The window is 1 year from liquidation. The standard is tight: legal errors and judgment calls do not qualify, only pure factual mistakes.

Can I stack these mechanisms?

No. CBP will reject duplicative filings. Sequence: PSC before liquidation, then protest within 180 days after liquidation, then 1520(c)(1) within 1 year of liquidation if a clerical error is discovered. For FTA preferential claims specifically, 1520(d) is the standalone path within 1 year of importation and should not be filed alongside a pending PSC or protest on the same issue.

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