Is the ban leaking? Hardwood plywood after the US Jan-2018 AD/CVD orders on China

Trade-flow companion to the price wedge (R72). DUAL-SCORE / alternative-track — never folded into any Tier-1 exposure score. The wedge measures scarcity; this desk measures the other half: is the control actually holding, or is the restricted trade re-entering the buyer by another door? Research, not investment advice. Circumvention is INFERRED from the structure of the flows plus public regulatory records, never asserted as evasion of any particular consignment.

Verdict

On 4 January 2018 the US published antidumping and countervailing duty orders on certain hardwood plywood products from China. Eight years later China's share of US plywood imports has gone from 41.8% to 2.6% while total US imports grew 19%. The volume did not disappear — it moved.

This case matters to the corpus for a reason that has nothing to do with plywood. Every other row in the circumvention register is an unadjudicated inference: we observe an implausible flow and say "consistent with". Here the US Department of Commerce ran the same question through a formal circumvention inquiry and published a verdict — affirmative for Viet Nam (20 July 2023), on the specific mechanism of Chinese face/back/core veneers assembled offshore. That gives us the corpus's first opportunity to score our own detector against a regulator's ground truth, and then to point it at the origins the regulator did not charge.

The detector passes. And where it disagrees with the enforcement perimeter, the disagreement is the finding.

The headline flow

Source: UN Comtrade free public preview API, reporter USA (842), flow M, annual, HS 4412. Reproduce: `https://comtradeapi.un.org/public/v1/preview/C/A/HS?reporterCode=842&period=2025&cmdCode=4412&flowCode=M`.

China −93%. Viet Nam +804%. Thailand +595%. The 2022→2023 fall in the world line is the post-COVID construction destocking, not the control — which is exactly why the share column, not the level, carries the signal.

The narrower scope-relevant subheading (HS 441233, plywood with a non-coniferous outer ply) says the same thing on the years it is fully reported: China $186.8m → $15.1m (2019→2025, −92%) while Thailand goes $10.3m → $81.9m (+695%) and Indonesia $68.5m → $310.6m.

Reading the input line — and the ratio that discriminates

The Xinjiang-cotton case established the diagnostic for this shape: read the INPUT line into the surger, not the finished-good origin line. Plywood is the ideal subject because its input has its own tariff heading — HS 4408, veneer sheets — so China's own export statistics report the feedstock directly.

Source: UN Comtrade, reporter China (156), flow X, annual, HS 4408 / HS 4412.

Look at the Cambodia rows. Between 2018 and 2021 China's finished plywood exports to Cambodia fell 98 → 33 while its veneer exports rose 14 → 111. The composition inverted. That is the customs signature of the last processing step moving across the border: the same group stops shipping the finished panel and starts shipping the plies, to be pressed on the far side of the duty line. Cambodia's own reporting corroborates the veneer leg independently — KH imports of HS 4408 from China $48.1m (2019) → $129.0m (2021) → $77.0m (2024), agreeing in direction and magnitude with China's export side (the residual gap is CIF-vs-FOB plus reporting lag).

Now the discriminating statistic. Divide the Chinese input flowing into a country by the plywood that country ships to the US — Chinese input available per dollar of US-bound shipment:

This is an upper bound on Chinese content, not an allocation — some of that input is consumed domestically, and the numerator is FOB China against an FOB-origin denominator. Read it as an exposure ratio, not a content share. Malaysia (154%) and Thailand (239%) in 2024 sit above 100% precisely because they are large furniture manufacturers absorbing Chinese panel for their own domestic production; the ratio flags them, it does not convict them.

But the ranking is the point. In 2019 Viet Nam was pulling in more Chinese plywood-and-veneer by value than its entire US plywood shipment. Indonesia has sat flat at 14–20% for six years.

The grade: what the regulator actually decided

• Viet Nam — charged and convicted. Commerce initiated a circumvention inquiry in

June 2020, published a preliminary affirmative determination on 29 July 2022, and a Final Scope Determination and Affirmative Final Determination of Circumvention applicable 20 July 2023. The finding names the mechanism precisely: Chinese-origin face veneers, back veneers, core veneers and assembled cores processed or assembled in Viet Nam are circumventing the China orders. Suspension of liquidation reaches back to the initiation date; a certification regime now governs the input's origin.

• Indonesia — never charged with circumvention. Indonesia is in the 2025–26

AD/CVD investigation, but for its own subsidies and dumping, not for laundering Chinese panel.

• Separately, CBP issued a Notice of Determination as to Evasion in EAPA

consolidated investigation 7252 (28 January 2022, final administrative decision 6 June 2022) on Chinese hardwood plywood entering through Viet Nam — the shipment-level enforcement leg beneath the Commerce finding.

So: our ratio ranked Viet Nam (105%) ≫ Cambodia (76%) ≫ Indonesia (20%) using nothing but two free Comtrade queries. The regulator convicted the top of that ranking and left the bottom alone. The input-ratio test reproduces an adjudicated outcome it was not fitted to. That is the first external validation any detector in this corpus has received, and it is the reason to trust the same test where no regulator has ruled.

It also fixes the boundary of mode C. Mode C (transformation-washing) is the case where a genuine process legally confers a new origin — Russian crude into Indian diesel. Plywood is the mirror image: physically the same shape (foreign input, offshore processing, new flag), but Commerce ruled the processing insufficient to confer origin. Call it C⁻ — the adjudicated-failed transformation wash. Between the Russian-crude row and this one, the corpus now brackets where the substantial-transformation line actually sits, with an input-ratio value attached to each side of it.

The finding: the perimeter was drawn by petition, not by fingerprint

The 2025–26 AD/CVD investigation — the repo's anchor action — covers China, Indonesia and Viet Nam. Preliminary CVD rates of 81.34% (China), 2.40–128.66% (Indonesia) and 4.37–26.75% (Vietnam) took effect 22 January 2026; final CVD determinations issued 21 July 2026, with the ITC injury ruling due 4 September 2026.

Cambodia is not in it.

Cambodia ships the US $264m of plywood a year (7.5% of imports, third among the Asian origins), on a Chinese-input ratio of 37% — roughly double Indonesia's, which is charged. Its Chinese veneer intake rose 7.9× between 2018 and 2021 while its Chinese finished-panel intake collapsed, the exact composition inversion Viet Nam showed before it was charged. No US circumvention inquiry has been opened on Cambodian plywood; the only Cambodia trans-shipment proceeding we could trace went to kitchen cabinets, and CBP did not find substantial evidence of evasion there.

We are not alleging Cambodian evasion. We are stating a structural fact about how these perimeters are set: AD/CVD scope is defined by who a domestic petitioner names, not by where the detector points. Commerce does not sweep for the highest input-ratio origin; it adjudicates the petition in front of it. So the enforcement perimeter systematically lags the flow by one hop — China (2018) → Viet Nam (2023) → China/Indonesia/Viet Nam (2026) — and the un-named origin with a failing ratio is, by construction, the cheapest door in the wall.

For a buyer, that inverts the usual reading of a duty order. A newly-charged origin is the safest origin, because it is now certified, audited and priced. The risk sits with the neighbour nobody filed against.

Transmission chain

`` US AD/CVD orders on Chinese hardwood plywood (4 Jan 2018; +Sec.301) → China's direct US line collapses 41.8% → 2.6% of imports (−93%) → China's exports to Viet Nam/Cambodia shift composition: finished plywood DOWN, veneer sheets (HS 4408) UP (KH: 14 → 111, 7.9×) → panels pressed in VN/KH from Chinese plies, exported as VN/KH origin → Commerce circumvention inquiry (Jun-2020) → affirmative final (20 Jul 2023): Chinese face/back/core veneers assembled in VN = circumvention; certification regime + retroactive suspension of liquidation → VN input-ratio falls 105% (2019) → 71% (2024): the remedy partially bit → new AD/CVD petition (Jun-2025) names CN + ID + VN; prelim CVD 22 Jan 2026, final 21 Jul 2026, ITC injury ruling due 4 Sep 2026 → Cambodia (ratio 37%, $264m/yr, composition already inverted) sits OUTSIDE the perimeter — the un-named hop ``

What it implies for the Tier-1 blind spot

A Tier-1 exposure score reading declared country-of-origin sees a US buyer whose Chinese plywood dependence fell from 42% to under 3% — a supply chain apparently de-risked. The input line says the panels are still substantially Chinese; only the pressing moved. On the 2024 ratios, a buyer sourcing "Vietnamese" plywood carries up to 71 cents of Chinese input per dollar of nominally non-Chinese purchase.

Two second-order consequences worth pricing:

1. The certification regime is the real cost, and it is retroactive. Suspension of liquidation reaching back to the inquiry's initiation date means an importer's liability crystallises years after the purchase order. Origin risk here is a balance-sheet item, not a procurement one. 2. Ratio, not flag, is the forward indicator. The origins whose Chinese-input ratio is high and whose composition has inverted toward veneer are the ones a future petition will name. That is a screenable, free, quarterly-updating list.

Caveats

• Inference, not proof. Every figure below the Commerce and CBP determinations is

a statistical structure, not evidence about any consignment. The Viet Nam leg is adjudicated; the Cambodia leg is explicitly not — it is an unadjudicated fingerprint and is presented as such.

• The ratio is an upper bound. Numerator and denominator are different flows with

different valuation bases (FOB China input vs FOB origin output) and no adjustment for domestic absorption. Malaysia and Thailand exceeding 100% demonstrates the limitation directly.

• HS 4412 is broader than the AD/CVD scope, which runs on specific HTS statistical

lines (4412.10.0500–4412.99.5710 with veneer conditions). We use the 4-digit heading because it is complete across the whole 2017–2025 window; the narrower 441233 line agrees but is unreliable for 2018 (HS2017 phase-in produced a partial world total) and is therefore not quoted for that year.

• Demand cycle contaminates levels. US plywood imports fell 41% from 2022 to 2023

on construction destocking. Shares are the honest comparison.

• No common-ownership tell was traced. Unlike the antimony (Youngsun → Thai Unipet)

or coltan cases, we found no public registry or filing linking a named Chinese producer to a named Vietnamese or Cambodian exporter of record. The Commerce determination is written about inputs, not ownership. This is a labelled gap, not a negative finding — it is the obvious next research step, and it is what would move Cambodia from fingerprint to pipe.

• Cambodia's own reporting is patchy in the free preview tier (the 2023 China line

is implausibly near-zero and the partner-World aggregate is missing in some years). We rely on China's export side as primary and use Cambodia's import side only as directional corroboration on the years it reports.

Sources

• UN Comtrade free public preview API — https://comtradeapi.un.org/public/v1/preview/C/A/HS;

reporter USA (842) flow M and reporter China (156) flow X, annual, HS 4412 / 4408 / 441233, periods 2017–2025. All trade figures above.

• Federal Register — *Certain Hardwood Plywood Products From the People's Republic of

China: Countervailing Duty Order*, 4 January 2018. https://www.federalregister.gov/documents/2018/01/04/2017-28481/certain-hardwood-plywood-products-from-the-peoples-republic-of-china-countervailing-duty-order

• Federal Register / GovInfo — *Certain Hardwood Plywood Products From the People's

Republic of China: Final Scope Determination and Affirmative Final Determination of Circumvention of the Antidumping and Countervailing Duty Orders*, 20 July 2023 (doc. 2023-15431). https://www.govinfo.gov/content/pkg/FR-2023-07-20/pdf/2023-15431.pdf

• US Customs and Border Protection — *EAPA Cons. Investigation Number 7252: Certain

Hardwood Plywood from the People's Republic of China*, Notice of Determination as to Evasion (28 January 2022) and Final Administrative Decision (6 June 2022). https://www.cbp.gov/document/publications/eapa-cons-investigation-number-7252-certain-hardwood-plywood-people-s-republic

• International Trade Administration (trade.gov) — initiation and final affirmative

AD/CVD determinations, Hardwood and Decorative Plywood from China, Indonesia and Vietnam (2025–2026). https://www.trade.gov/final-affirmative-determination-antidumping-and-countervailing-duty-investigations-hardwood-and

• Repo anchor action: docs/iptm/actions/2026-01-22-us-doc-hardwood-plywood-china-indonesia-vietnam-countervailing-duty-preliminary.md

(preliminary CVD rates, final-determination amendment, ITC ruling date).