Ministry of Commerce Spokesperson on Anti‑Circumvention Ruling for US‑Origin Optical Fiber Imports — Q&A

anti‑circumvention ruling for US‑origin optical fiber imports

• Investigation Initiated: March 4, 2025 by Ministry of Commerce (Shangwu Bu 商务部), following application by domestic Chinese companies.
• Investigation Findings: Evidence shows US-origin cutoff-wavelength shifted single-mode optical fiber used to evade anti-dumping duties on non-dispersion-shifted single-mode optical fiber.
• Measures Effective Date: September 4, 2025, with enhanced customs scrutiny.

• Originally Subject to Anti-Dumping Duties: Non-dispersion-shifted single-mode optical fiber (非色散位移单模光纤)
• Circumventing Product: Cutoff-wavelength shifted single-mode optical fiber (jiezhi bōcháng wèiyí dānmó guāngxiàn 截止波长位移单模光纤)
• Origin: United States (Meiguo 美国)

Stakeholder Impact Summary

Stakeholder Group	Key Impact / Action Required	Reasoning
Importers (China)	Enhanced customs scrutiny; re-review contracts and procurement for tariff clauses.	To reflect potential additional duties and ensure compliance.
US Exporters	Update compliance playbooks; reassess product specifications and customs classifications.	Product variations can now trigger anti-circumvention countermeasures.
Investors	Revisit due diligence on optical fiber supply chains.	Companies reliant on cross-border components face increased regulatory risk.
Domestic Chinese Fiber Producers	May see short-term relief.	From lower-priced imports that were previously undercutting domestic prices.
Legal Teams	Prepare documentation proving technical differences/sameness of products.	Cases often hinge on technical specifications and evidence.

Question

We noticed the Ministry of Commerce (Shangwu Bu 商务部) announced anti‑circumvention measures targeting certain optical fiber products originating in the United States (Meiguo 美国).

Can you explain the situation?

Answer

On March 4, 2025, at the request of domestic Chinese companies, the Ministry of Commerce (Shangwu Bu 商务部) launched an anti‑circumvention investigation into imports originating in the United States of certain cutoff‑wavelength shifted single‑mode optical fiber (jiezhi bōcháng wèiyí dānmó guāngxiàn 截止波长位移单模光纤).

This case marks China’s first anti‑circumvention investigation.

After the case was filed, the Ministry conducted its investigation in accordance with law and procedure.

The process was open and transparent and fully protected the rights of all interested parties.

The investigation found evidence that US exporters circumvented China’s existing anti‑dumping measures on non‑dispersion‑shifted single‑mode optical fiber (fei sè­sàn wèiyí dānmó guāngxiàn 非色散位移单模光纤) by exporting related cutoff‑wavelength shifted single‑mode optical fiber to China.

Based on the investigation’s findings, the Ministry of Commerce announced it would implement anti‑circumvention measures.

Those measures take effect on September 4, 2025.

Key points (brief)

• This investigation was initiated on March 4, 2025, following an application by domestic enterprises.
• It is China’s first anti‑circumvention probe.
• The evidence indicates US exports of cutoff‑wavelength shifted single‑mode optical fiber were used to evade anti‑dumping duties on non‑dispersion‑shifted single‑mode optical fiber.
• Anti‑circumvention measures announced by the Ministry of Commerce take effect September 4, 2025.

What happened — plain and simple

Anti‑circumvention inquiries ask whether a product has been altered just enough to avoid an existing trade remedy.

In this case, the Ministry found that certain US‑origin fibers were being moved into China under a closely related product definition to avoid anti‑dumping duties on the original product.

That led to China invoking its first-ever formal anti‑circumvention mechanism to close the gap.

Why this matters to investors, founders, and supply‑chain operators

• Market access: Companies importing affected optical fiber types into China should assume enhanced customs scrutiny starting September 4, 2025.
• Pricing & contracts: Procurement teams should re‑review contracts that name these fiber types and add clauses for tariffs, duties, and compliance costs.
• Compliance risk: Exporters from the US should update compliance playbooks to reflect that such product variations can trigger anti‑circumvention countermeasures.
• Domestic competitors: Chinese fiber producers who filed the request may see short‑term relief from lower‑priced imports that were previously undercutting domestic prices.
• Legal precedents: This sets a formal precedent in China for applying anti‑circumvention rules — expect more such cases in other industries where product tweaking is used to avoid duties.

Action checklist for relevant stakeholders

• For US exporters: Reassess product specifications and customs classifications for shipments to China.
• For Chinese importers: Confirm whether existing purchase orders include the affected cutoff‑wavelength shifted single‑mode optical fiber types.
• For legal teams: Prepare documentation proving the technical differences or sameness between the affected fibers and the previously regulated product.
• For investors: Revisit due diligence on optical fiber supply chains, especially for companies reliant on cross‑border components.
• For marketers & business development: Update go‑to‑market plans for China to reflect potential cost increases or supply changes after September 4, 2025.

How to read the Ministry’s move strategically

This is a trade‑defense tool used to preserve the intent of anti‑dumping duties.

It signals that Chinese regulators will actively police product reclassification and technical tweaks meant to skirt tariffs.

For global supply chains, this increases the importance of clear product taxonomy, transparent declarations, and robust technical documentation.

Legal & regulatory context — short primer

• Anti‑dumping duties: Applied when imports are sold at less than fair value and injure domestic industry.
• Anti‑circumvention investigations: Target altered products or minor changes intended to evade existing trade remedies.
• Technical evidence: These cases often hinge on technical specs — so product datasheets, test reports, and expert testimony matter.

Keyword & SEO opportunities

Target keywords: anti‑circumvention ruling, US‑origin optical fiber imports, cutoff‑wavelength shifted single‑mode optical fiber, anti‑dumping China.

Potential internal link targets for further coverage:

• Trade policy & regulations — explain how anti‑dumping and anti‑circumvention work.
• Supply‑chain compliance playbook — documentation and classification best practices.
• China telecoms & fiber market — landscape and major players.

Takeaways

1. This is China’s first formal anti‑circumvention probe, triggered March 4, 2025, and effective September 4, 2025.

2. The Ministry of Commerce (Shangwu Bu 商务部) found evidence that US‑origin cutoff‑wavelength shifted single‑mode optical fiber was used to evade anti‑dumping duties on non‑dispersion‑shifted single‑mode optical fiber.

3. Stakeholders should update compliance, procurement, and commercial plans now to reflect increased scrutiny and potential additional duties.

4. This ruling signals a tighter regulatory stance from China on technical product reclassification and trade remedy circumvention.

anti‑circumvention ruling for US‑origin optical fiber imports

References

• Q&A: Ministry of Commerce Spokesperson on Anti‑Circumvention Ruling – Ministry of Commerce
• Ministry of Commerce spokesperson answers reporters on anti‑circumvention ruling on US‑origin optical fiber imports – Eastmoney