Japan extends anti-dumping duty on South Korean dipotassium carbonate by 5 years following sunset review

Mechanism

This is a sunset-review continuation, not a new duty. The original 30.8% anti-dumping duty on Korean-origin dipotassium carbonate ran 2021-06-24 to 2026-06-23 (Cabinet Order No. 65 of 2021, under Customs Tariff Act Art. 8). Domestic producer AGC Inc. petitioned in June 2025 for an extension ahead of the sunset date; MOF and METI opened a joint investigation in August 2025 and found a continuing/recurring risk of dumping and material injury to the domestic industry. On 2026-06-23 the Customs Tariff Council's special-duties subcommittee (関税分科会特殊関税部会) recommended a 5-year extension to the Finance Minister; the Cabinet decided to extend on 2026-07-03, and the amending order was promulgated 2026-07-08, effective 2026-07-09, pushing the duty period out to 2031-07-07 at the same 30.8% rate.

Downstream implications

• Continuation, not escalation: rate is unchanged, so this doesn't raise

landed cost for Korean exporters further, it just removes the near-term sunset date they may have been pricing in.

• Protects AGC Inc.'s domestic potassium-carbonate production (an input to

LCD/display-glass and detergent manufacturing) from Korean import competition through mid-2031.

Open questions

• Named Korean exporter(s)/producer(s) subject to the duty are not disclosed

in the press release or the consolidated order text pulled here — the original 2021 investigation record (not fetched this pass) likely names them.