C114 News, February 11, 2026. According to the China Trade Remedy Information Network, on January 22,2026, the Korea Trade Commission issued Announcement No. 2026-1 (Case Investigation No. 23-2025-1, making a final affirmative determination of anti-dumping on single-mode optical fiber (Single Mode Optical Fiber) originating in China. It is recommended that the Ministry Planning and Finance of Korea impose anti-dumping duties for a period of five years on Hengtong Optic-Electric Co., Ltd. and its related enterprises, Yangtze Optical Fibre and Cable Joint Stock Limited Company and its related enterprises, Hangzhou Jinxingtong Optical Fiber Technology Co., Ltd. and its enterprises, as well as other Chinese manufacturers/exporters, all at a rate of 43.35%.

This case involves products classified under Korean tax number 9001.10.0000, excluding low-loss optical fiber, optical cables, and single-mode optical fibers with a specification of G.652.D mainly used for optical devices.

Previously, on March 7,2025, Korea initiated an anti-dumping investigation on single-mode optical fibers originating in China, with the investigation period for dumping from July 1, 223, to June 30, 2024, and the investigation period for injury from January 1, 2021, to December 31 2024.

On September 19, 2025, the Ministry of Planning and Finance of Korea decided to impose a provisional anti-d duty on the products from China involved in the case for a period of 4 months, from September 19, 2025, to January 18,2026.

On December 30, 2025, the Ministry of Planning and Finance of Korea announced the extension of the provisional anti-d duty on single-mode optical fibers from China for an additional 2 months, changing the period from September 19, 2025, to January 18 2026 (4 months) to September 19, 2025, to March 18, 2026 (6 months).