1. Overview : A new anti-circumvention system

In connection with the 2026 annual revision of the Customs Act and related legislation (the "2026 revision"), Japan has introduced and implemented a new anti-circumvention system (the "System"), which entered into force on April 1, 2026.

Historically, Japan has taken a cautious stance toward establishing an anti-circumvention framework. However, as other jurisdictions have adopted such systems to ensure the effectiveness of the Anti-Dumping Duty (AD), Japan has now recognized the necessity of introducing its own framework. The shift aims to strengthen the effectiveness of the AD measures and to prevent the inflow of unfairly priced goods.

An outline of the System can be broadly set out in 3 components: (1) types of circumvention, (2) requirements for applying duties to circumvented goods, and (3) investigation procedures.

(1) Types of Circumvention

The System covers the following 3 types of circumvention:

• Third country circumvention:
  Circumvention in which the country of origin is changed by exporting goods from the country subject to AD measures to a third-party country, where further processing is conducted.
• Minor modification circumvention:
  Circumvention in which the HS Code classification is changed through minor processing in the country subject to AD measures.
• Circumvention from the importing country:
  Circumvention in which the product is imported in an almost finished form and undergoes final processing in Japan.

The applicability of the above types of circumvention will be determined on a case-by-case basis, taking into account various factors.

(2) Requirements for applying duties to the circumvented goods

Under the System, when an existing AD measure (the "Original AD") is circumvented through changes in the supplying country or product, the Original AD may be extended to the circumvented goods as an extension or supplement to the Original AD.

Specifically, requirements are established for each type of circumvention. Where (a) the existence of circumventing imports can be established, and (b) material injury to the domestic industry caused by such imports is confirmed, the circumvented goods will be subject to the duties applied through the Original AD.

To ensure expeditious procedures, if the export price of the circumvented goods is lower than the normal value established in the Original AD, such imports may be treated as dumped, and the dumping margin will not be recalculated.

(3) Anti-Circumvention Investigation Procedures

Under the anti-circumvention investigation procedures, a final decision on whether to impose duties will be made within 10 months, in principle, from the date of initiation of the anti-circumvention investigation. This is shorter than the usual period of investigation for AD measures, which is in principle 1 year.

On April 24, 2026, the Ministry of Economy, Trade and Industry, which is responsible for the anti-circumvention investigation, together with the Ministry of Finance, published their "Guidelines for Applicants for the Anti-Circumvention System". Applicants are advised to refer to these Guidelines when filing an application for anti-circumvention duties.

2. Other developments under the 2026 revision

In addition to the above, the 2026 revision introduced several measures to address a rapid increase in the number of low-value imported goods to Japan. For example, the government decided to abolish, as of April 1, 2028, the special valuation rule for personal use items that, at the time of writing, sets the taxable value at 60% of the overseas retail price.

Businesses engaged in international trade would do well to carefully review the 2026 revision.