Changelog

Duty rows whose rate text we could not previously read have been re-parsed through the
current grammar and now carry structured components, constraints or a reference target.

No rate value was invented. Every component is derived from the verbatim USITC text, and
any rate that could not be read in full is still reported as unreadable rather than
partially. Where a rate depends on something only the importer knows, we publish the terms
and decline to total them.

Ten watch and clock headings had been storing only the first two terms of a three-term
rate, which under-reported their duty. They now carry all three terms and are marked as
not machine-totallable.

Two correctness fixes and a large coverage improvement.

A duty carrying both a percentage and a per-unit component was classified from a
denormalised `compound_rate` flag rather than from the components themselves. When a
data load set the components without the flag, the rate was demoted to `specific` and its
ad valorem side was silently dropped. Thirteen headings were affected, including
`9606.21.40.00` (buttons), whose rate is 4.6% plus 0.3 cents per line per gross.

Separately, ten watch and clock headings had been storing only the first two terms of a
three-term rate, which under-reported their duty.

The rate parser gained coverage for rate shapes it had always refused:

* Chapter 99 special-column rates qualified by a trade program, such as "$1.41/kg (PA)".
* Missing unit aliases: per metre, per linear metre, per pack, per article, per jewel,
per line per gross, per thousand pins.
* Rates with three or more terms, and rates charged on a metal content, a component of the
article, the fair retail value or the cost of repairs.
* The polarimeter-degree sugar formulas of Chapter 17, including their floors.
* Cross-references to another heading, subheading or U.S. note.
* Damage introduced by the source extraction, such as a soft-hyphen break inside a word.

Duties whose rate text contains a number and which we could not parse fell from 203 to 2.
A further 90 headings state their rate in words alone, with no number at all; those are
covered in V.1.0.7.

When a base duty could not be parsed, the API returned
`rate_type: "ad_valorem", percentage_component: null`, and `summary.notes` said
"Base duty is 0%" alongside `confidence.score: 1.0` and an empty `warnings` array. Any
client that reads a null percentage as zero computed a duty-free base. Our own AI tools
rendered those headings as "Free".

This affected 91 general-column headings, including beet sugar, and the lead, molybdenum,
tungsten and magnesium ores.

A base duty that is not a plain number now says so, on every endpoint including
`resolve_batch`:

* `summary.base_rate_known: false` — `applicable_ad_valorem_rate` excludes the base duty
and is a lower bound.
* `warnings[]` carries one of `BASE_RATE_UNPARSED` (we could not read it),
`BASE_RATE_NOT_CALCULABLE` (we read it but it needs inputs only you hold) or
`BASE_RATE_REFERENCE` (it defers to another heading or note), each with the source text
and, where relevant, `inputs_required` or `refers_to`.
* `confidence` gains a fourth factor, `base_rate`, which drops the score to 0.5.

A specific duty is no longer described as "Base duty is 0%" either. A rate of 68 cents per
head has no ad valorem component, but it is not a zero duty, and the note now says so.

`applicable_ad_valorem_rate` is unchanged in shape and remains a number.

`base_tariff.rate_type` previously returned only `ad_valorem`, `specific` or `compound`.
Three values have been added, and each one replaces a case that used to be reported
misleadingly as `ad_valorem` with a null rate:

* `formula` — we read the rate but cannot total it without inputs only you hold. Carries
`components[]`, `constraints[]`, `inputs_required` and `raw_rate`.
* `reference` — the heading defers to another heading, subheading or U.S. note. Carries
`refers_to` and `raw_rate`.
* `unparsed` — we could not read the rate at all. Carries the verbatim USITC text in
`raw_rate`.

If your integration switches on `rate_type`, add these three cases. A response with
`rate_type` of `formula`, `reference` or `unparsed` has a null `percentage_component`,
and a null percentage is not a zero percentage. A `formula` rate deliberately exposes no
scalar at all: for `1.7 cents/kg on lead content`, a `per_unit_component` of 0.017 would
invite you to multiply by total kilograms when the correct multiplicand is the lead
kilograms.

The API path is unchanged and remains `/api/v1`.

Some US HTS headings carry a base duty that a single number cannot express. A watch
movement is dutiable at "36 cents each + 5.6% + 2 cents per jewel". Lead ore is dutiable
per kilogram of lead content, not per kilogram of ore. Beet sugar is dutiable per
kilogram, reduced for every polarimeter degree under 100, with a floor. Until now the API
had only two fields for a rate, `percentage_component` and `per_unit_component`, so these
headings had no honest representation.

`base_tariff` now carries five new fields:

* `components[]` — every term of the rate, as `{kind, value, unit, basis}`. `kind` is
`specific` or `ad_valorem`. `basis` appears only when the term applies to something
other than the entered value or the entered quantity, for example `lead_content`,
`battery`, `fair_retail_value` or `degree_under_100`.
* `constraints[]` — floors and caps, for example `{"kind":"floor","value":0.03143854,"unit":"kg"}`
or `{"kind":"cap","basis":"complete_movement"}`.
* `duty_calculable` — `false` when the duty cannot be totalled from entered value and
entered quantity alone.
* `inputs_required` — what you must supply when `duty_calculable` is `false`, for example
`[{"name":"polarimeter_degrees","unit":"degree"}]`.
* `refers_to` — for headings that name another heading or a U.S. note instead of stating a
rate, for example `{"kind":"heading","targets":["2009"]}`.

These fields are additive. `percentage_component` and `per_unit_component` keep their exact
meaning for ordinary ad valorem, specific and compound rates.

We describe these rates. We do not total them, and we do not follow a reference to another
heading. The jewel count of a movement, the copper content of an ore and the polarimeter
reading of a sugar shipment are facts only the importer holds. Guessing at them would
produce a confident wrong number.

tariff-rate-quota administration; quotas are outside our rate model.

A quarterly tariff-rate-quota bulletin for UK automobiles. We report duty rates, not quota quantity administration, so nothing changes in our data.

processing mechanics for refunding already-collected IEEPA duties; no rate change.

CBP updated the tool importers use to claim refunds of already-collected IEEPA duties (reconciliation-flagged entries). This is refund-processing workflow, not a change to any rate we serve.

USDA organic-program HTS flagging and filing reminders; no duty-rate change.

USDA's Agricultural Marketing Service updated HTS flagging and filing reminders for the National Organic Program. This is a filing requirement, not a rate change.

deployment confirmation of the IEEPA refund-processing tool; no rate change.

CBP confirmed the IEEPA refund tool (reconciliation-flagged entries) is now live in the ACE Portal. This is refund-processing workflow, not a change to any rate we serve.

filing instructions for the per-importer, Commerce-granted Section 232 auto/MHDV parts duty offset; changes no rate or scope.

CBP explained how importers claim the Section 232 import-adjustment offset on automobile and medium/heavy-duty-vehicle parts. The offset is a per-importer allowance granted by the Commerce Department; the underlying Section 232 rates are unchanged.

new ACE error code (F876); system-processing only.

CBP added a new ACE error code governing how duty and non-duty HTS lines are filed together. This is entry-processing validation, not a rate change.

Harmonized System Update; HTS code changes are ingested automatically by the USITC scrape, no manual data change.

CBP deployed Harmonized System Update 2614. HTS code additions and edits from these updates are picked up automatically by our data pipeline.

tariff-rate-quota restraint limit; quota administration is outside our rate model.

A tariff-rate-quota bulletin setting the final tuna restraint limit and proration. We report duty rates, not quota administration, so nothing changes in our data.

entry-type eligibility rules for the IEEPA refund tool; no rate change.

CBP updated which entry types (warehouse entries and withdrawals) route through the IEEPA refund tool. This is refund-processing eligibility, not a change to any rate we serve.

Paperwork Reduction Act notice extending the court-ordered IEEPA refund worksheet; no rate change.

A Paperwork Reduction Act notice seeking comment on extending the worksheet importers use to claim court-ordered IEEPA refunds. This concerns paperwork burden only, not any duty rate.

Section 232 investigation of anthracite/metallurgical coal at the public-comment stage; no duty imposed.

The Commerce Department opened a Section 232 investigation into anthracite and metallurgical coal imports (HTS 2701.11 and 2701.12) and is taking public comment through July 21, 2026. No duty is imposed at this stage, so no rates change. We will update if it results in tariffs.

The 2024 four-year review raised Section 301 duties on five specific 10-digit facemask codes under heading 6307.90.98. Between June 15 and July 6 our data applied that increase to the whole heading, overstating China-origin totals on non-mask articles (for example 6307.90.98.91) at 42% instead of 24.5%, or 17% where a product exclusion applies. Corrected on July 6: non-mask codes now return List 4A treatment, facemask codes are unchanged at their current 50% rate, and historical lookups for 2024-2025 reflect the rates in force at the time. We also added expiry dates to all reinstated product exclusions (heading 9903.88.69), which run through November 9, 2026.

The July 1 HTS revision split 24 tariff lines into new 10-digit statistical codes (including 8708.80.16, 1702.90.90, 2209.00.00, 3507.90.70, 9404.10.00). Our importer briefly reported those new codes without their China Section 301 duty, under-stating totals by 25 percentage points on affected China-origin lookups. Fixed on July 4: all 24 families now return the full duty stack, the importer anchors Section 301 at the 8-digit line so future revisions inherit automatically, and a structural audit now flags this pattern before it can recur.

Proclamation 11038 authorizes (does not self-execute) temporary duty-free entry of Moroccan phosphate fertilizer under Tariff Act Section 318; names no HTS and targets AD/CVD, which we do not model.

Proclamation 11038 authorizes temporary duty-free entry of phosphate fertilizer from Morocco, to be implemented later by the Treasury and Commerce Departments. It names no HTS codes and points at countervailing-duty relief, which is outside our rate model, so no rates in our data change.

USITC published 2026HTSRev11 and it is now live in the API. 89 rates changed.

Imports from Cuba, North Korea, Russia, and Belarus now correctly resolve at Column 2 rates per General Note 3(b) instead of Column 1, with applicable surcharges stacking on top.

We have added a new way to discover HTS codes, our AI agent trained on our entire database will be able to help you discover and understand HTS codes.

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Goods of US origin no longer receive Section 232 or Section 122 additional duties on re-import lookups. These import remedies never applied to US-origin goods; our data now reflects that consistently.

Added the Section 301 four-year review increases under headings 9903.91 (415 code and origin rows; for example aluminum wire 7608.20.0030 from China moved from 55.7% to 80.7%). Also applied the 15% Section 232 auto-parts caps for EU, Japan, Korea, and Taiwan origins.