On June 15, 2026, the Supreme Court quietly ended the biggest tariff lawsuit in U.S. history with a one-line order. If you import from China and were counting on a refund for List 3 or List 4A duties, that money now belongs to the government — permanently. Here's what happened, what it means for your bottom line, and where the only remaining relief options are.
Six years. Over 3,600 lawsuits. Hundreds of billions in duties collected. And it all ended not with a bang, but with a single sentence on the Supreme Court's weekly orders list: certiorari denied.
On June 15, 2026, the Court declined to hear HMTX Industries, LLC v. United States, the test case that represented every importer who believed the U.S. Trade Representative overstepped its authority when it expanded Section 301 tariffs from $50 billion to $370 billion worth of Chinese goods. The importers' core argument — that USTR's "modification" power didn't authorize a sevenfold expansion of the original trade action — never even got a hearing on the merits.
For companies like HMTX Industries (a luxury vinyl flooring importer), Jasco Products, Halstead New England, and Metroflor Corporation, the denial is the final stop. But they weren't alone. Behind those four named plaintiffs stood an army of 3,600 importers who filed nearly identical complaints, hoping that if HMTX won, they'd all get refunds on years of accumulated 25% and 7.5% duties.
That hope is now officially dead.
How $50 Billion Became $370 Billion
The Section 301 tariffs trace back to a 2017 USTR investigation into China's technology-transfer and intellectual-property practices. The investigation concluded that China's policies caused at least $50 billion per year in harm to U.S. businesses. USTR's response came in waves:
| List | Products Covered | Annual Trade Value | Rate | Effective Date |
|---|---|---|---|---|
| List 1 | Industrial machinery, electronics, aerospace | $34 billion | 25% | July 2018 |
| List 2 | Semiconductors, plastics, chemicals | $16 billion | 25% | August 2018 |
| List 3 | Furniture, auto parts, building materials | $200 billion | 25% | September 2018 |
| List 4A | Consumer goods, apparel, footwear | $120 billion | 7.5% | February 2020 |
Lists 1 and 2 were never seriously challenged — they roughly matched the $50 billion in identified harm. The lawsuit targeted Lists 3 and 4A specifically because they expanded the action by roughly $320 billion, far exceeding the damage USTR itself had quantified.
The Legal Argument That Almost Worked
The importers' case wasn't frivolous. Section 307 of the Trade Act of 1974 allows USTR to "modify or terminate" a Section 301 action. The plaintiffs argued that "modify" means making adjustments to an existing action — not multiplying its scope by seven.
Think of it this way: if your landlord's lease says they can "modify" your rent, does that authorize them to increase it from $1,000 to $7,000? The importers said no. The government said the word "modify" places no ceiling on the size of the change, only that it must relate to the original investigation.
The Court of International Trade (CIT) initially wavered. In 2022, it remanded the case back to USTR, ordering the agency to better explain its reasoning. USTR complied with a supplemental explanation, and the CIT upheld the tariffs in 2023.
The Federal Circuit affirmed on September 25, 2025, ruling that Section 307(a)(1)(C) authorized USTR to modify the action when China's retaliatory tariffs increased the "burden or restriction" on U.S. commerce. In other words, because China hit back after Lists 1 and 2, USTR was justified in escalating.
The Supreme Court's denial of certiorari doesn't endorse this reasoning — but it doesn't need to. The practical effect is identical to a loss: the Federal Circuit's decision stands as the final word.
What This Means for Your Refund Claims
If you filed a "me-too" lawsuit: Your case is over. The claims in all 3,600+ consolidated cases were based on the same legal theories that the Federal Circuit rejected. Absent extraordinary circumstances, these cases will be dismissed.
If you filed protests with CBP: Protests arguing that List 3 and 4A tariffs were unlawfully imposed will be denied. CBP has no basis to grant relief on legal theories the courts have conclusively rejected.
If you were waiting to see what happened: The statute of limitations for filing a Court of International Trade action is two years from the date of liquidation. If your entries liquidated more than two years ago and you never filed, there is no mechanism to recover those duties now.
Important distinction: This case is entirely separate from IEEPA tariff refunds. The Supreme Court's February 2026 ruling striking down IEEPA tariffs and the subsequent CAPE refund program operate under completely different legal authorities. If you're owed an IEEPA refund, this decision has zero impact on that claim.
The Permanent Cost of Importing from China
With the legal challenge dead, importers need to internalize a reality that many had treated as temporary: Section 301 tariffs on Chinese goods are a permanent feature of the trade landscape.
The total duty burden on a Chinese-origin product can now stack multiple layers:
| Duty Layer | Rate Range | Authority |
|---|---|---|
| MFN (baseline) duty | 0% – 20%+ | HTS Column 1 |
| Section 301 (original lists) | 7.5% – 25% | Trade Act of 1974 |
| Section 301 (four-year review additions) | 25% – 100% | Trade Act of 1974 |
| Section 232 (if steel/aluminum/copper) | 25% – 50% | Trade Expansion Act |
For a product on List 3 with a 5% MFN rate, you're paying 30% total — and that's before any Section 232 overlay. For products hit by the 2024 four-year review increases (EVs at 100%, medical gloves at 100%, semiconductors at 50%), the numbers are staggering.
The 178 Exclusions: Your Only Administrative Relief
The sole remaining administrative relief from Section 301 tariffs is the product exclusion program. Currently, 178 product-specific exclusions remain active, extended through November 10, 2026 as part of the Trump-Xi agreement reached at the November 2025 summit.
These exclusions are claimed using specific HTSUS subheadings. If your product qualifies, you pay no Section 301 duty — but the list is narrow, and USTR has historically been stingy about adding new exclusions.
More significantly, USTR launched its second four-year review of the Section 301 tariffs in May 2026. This review could theoretically result in:
- New product exclusions
- Rate adjustments (up or down)
- Expansion to additional products
But based on the trajectory — the first four-year review in 2024 only raised rates — importers shouldn't expect relief from this process.
What to Do Now: Five Action Steps
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Audit your Section 301 exposure — Identify every HTS code in your import portfolio that falls on Lists 1–4A or the four-year review additions. Calculate your actual total duty burden including all stacking tariffs.
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Review your classification accuracy — With 25% riding on whether a product falls on a Section 301 list, classification errors are enormously expensive. A product classified under an HTS code on List 3 at 25% might properly belong under a code that isn't listed at all. This is where precision matters most.
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Check the 178 active exclusions — Cross-reference your imports against the current exclusion list before it expires November 10, 2026. If you qualify and haven't been claiming the exclusion, you may be able to file protests for entries within the protest window.
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Evaluate supply chain alternatives — With no legal path to refunds and no realistic prospect of tariff reduction, the economics of sourcing from Vietnam, India, Malaysia, or Mexico should be recalculated using the confirmed permanent rate — not a discounted "maybe it goes away" rate.
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Participate in the second four-year review — USTR's May 2026 review is accepting public comments. If your product faces a tariff that demonstrably harms U.S. manufacturing or has no domestic alternative, this is your only channel for potential relief.
What's Coming Next
Three developments to watch in the next 90 days:
November 10, 2026: The 178 Section 301 exclusions expire. Whether USTR extends them again — and whether the Trump-Xi agreement framework survives the current geopolitical climate — is an open question.
Second four-year review timeline: USTR typically takes 6–12 months to complete a review. Expect proposed modifications by late 2026 or early 2027. Based on the first review, which added 100% tariffs on EVs and batteries, "modification" is more likely to mean increases than decreases.
Section 301 forced labor tariffs: Separately, USTR proposed new Section 301 tariffs of 10–12.5% on imports from 60 economies linked to forced labor. If finalized, these stack on top of existing duties — including the China Section 301 tariffs this case just confirmed.
The Classification Imperative
Here's the lesson that makes this ruling actionable rather than just depressing: when tariffs are permanent and rates are this high, classification accuracy becomes the single highest-ROI compliance activity you can perform.
A misclassified product that lands on List 3 when it shouldn't be there costs you 25% on every shipment, compounding over years. A product that genuinely qualifies for an exclusion you never claimed is money left on the table. And with total effective rates on some Chinese goods exceeding 75%, even a small classification adjustment — moving from one HTS subheading to another — can mean six- or seven-figure annual savings.
The HMTX fight is over. The tariffs aren't going anywhere. The only question left is whether you're paying the right amount — and that comes down to getting your classification right.
This article is for informational purposes only and does not constitute legal, tax, or customs advice. Consult a licensed customs broker or trade attorney for guidance specific to your situation.