The reasoning sounds solid the first time you hear it. A trade measure hits goods of Chinese origin; you move the final assembly to a plant in Vietnam, Thailand or Malaysia; the goods leave that plant, so they are of that country's origin, so the measure does not apply. Every step of that chain is wrong except the first. Origin is not conferred by the place of departure, by the address on the invoice, or by the flag of the plant. It is conferred by a rule, and the rule looks at what was done to the goods. And the rule is not a matter of opinion: it is published, product by product, and an investigator will read the same text you could have read first.
What actually confers origin on a product
When a product is made in more than one country, it takes the origin of the country where it underwent its last substantial transformation. That phrase is not a slogan; it is given content by product-specific rules, and the content differs from one family of goods to the next. Several mechanisms are used, sometimes alone, sometimes combined, and which one applies to your article is a question with a written answer that you have to go and read.
- A change of tariff classification. The rule requires the finished article to fall under a different heading from the materials that went into it. If the parts arrive already classified where the finished product is classified, assembling them confers nothing, however much labour it takes.
- A share of local value added. The rule sets the proportion of the value that must be created in the country, or caps the share that may come from non-originating materials. The calculation uses defined values — the price of the materials, the price of the finished product at the factory gate — and it is audited against accounts, not against estimates.
- A specific processing operation. For some products the rule names the operation itself: a chemical reaction, a weaving step, a particular forming process. Doing something else, even something more expensive, does not satisfy it.
- And a list of operations that never count. Packing, repacking, labelling, sorting, simple mixing, simple assembly, affixing marks: these are insufficient operations by definition. A plant that only does them is a transit point with a roof on it, and that is exactly how an investigator will describe it.
Why moving a final step is itself a subject of investigation
The European Union does not treat the relocation question as a matter of interpretation to be settled quietly between an exporter and a customs office. It has a dedicated instrument for it: an anti-circumvention investigation, opened when there are indications that a trade measure is being evaded by routing goods through a country outside the Union, by shipping them in parts for assembly, or by slightly modifying the product. The investigation looks at when the operation started relative to the measure, whether the business has any justification other than the duty, and what proportion of the value and the parts actually comes from the country under measure.
The consequence, if circumvention is found, is that the measure is extended to imports from that country — and it can be made to reach back to goods that were registered while the investigation was running. Which means the commercial calculation that justified the move disappears, and the company is left with a plant abroad, an extended measure, and an importer asking who pays. A plant opened for real industrial reasons, with real transformation and a real local supply chain, has a case to make. A finishing line opened the season a measure landed has a much harder one.
What a certificate of origin proves, and what it does not
A certificate of origin is a declaration, not a verdict. Whoever issues it — a chamber of commerce, an authority, or the exporter itself under a self-certification scheme — is attesting to what was declared to them. It does not bind the European customs administration, which may verify the substance behind it, ask the issuing country to check its records, and refuse the claim if the vérification fails or simply goes unanswered. Preferential certificates, which claim a reduced duty under a trade agreement, are verified more often than ordinary ones, because something is at stake.
And a distinction worth holding on to, because confusing them produces real losses: preferential origin and non-preferential origin are separate questions with separate rules. Preferential origin decides whether a reduced rate under an agreement applies. Non-preferential origin decides where the goods are from for the purposes of trade defence measures, labelling and statistics. A product can qualify as originating under an agreement and still be of Chinese origin for the purpose of an anti-dumping measure. A certificate answering one question has not answered the other.
How an honest exporter documents its position
- Find the rule that applies to your heading, and write it down. Not the general principle: the product-specific rule, for the agreement or the regime concerned. It is published. Copy it into the file, because everything that follows is built to answer it.
- Build the bill of materials with origins attached. Every component, its supplier, its own classification and its own origin, with the purchase documents behind it. A bill of materials without origins is a production document, not an origin file.
- Collect supplier declarations. Where the rule depends on the origin of a material, you need the supplier's written statement of that origin, kept for as long as the records must be retained. Relying on the supplier's word on the telephone is how an otherwise valid claim collapses during verification.
- Do the calculation, and keep the version that was used. If the rule is a value rule, the computation has to be reproducible from the accounts, for the period concerned. Prices move; a calculation that was true at one point and was never recorded cannot be defended afterwards.
- Consider a binding origin decision for the articles that matter. European customs law allows origin, like classification, to be fixed in advance by a written decision binding on the administrations of the Member States. It is the only way to stop re-arguing the same question at every port.
If you are considering production in an ASEAN country, run the origin rule before signing the lease, not after the first container. Take the heading of the finished product, read the product-specific rule, list what each component would cost and where it would come from, and see whether the rule is met with the supply chain you can actually build locally. If it is met only on paper, or only if certain parts stop coming from China, you have found the real industrial decision — and it is a sourcing decision, not a legal one.
Where to read it yourself
Official pages, opened and checked on 15 October 2026. Where a rule changes, these are the addresses that change with it — this article does not.