# 1-Hydroxyethylidene-1, 1-Diphosphonic Acid From the People's Republic of China: Final Affirmative Determination of Circumvention
**AGENCY:**
Enforcement and Compliance, International Trade Administration, Department of Commerce.
**SUMMARY:**
The U.S. Department of Commerce (Commerce) determines that imports of acidic (non-neutralized) concentrations of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP), also referred to as hydroxyethylidenendiphosphonic acid, hydroxyethanediphosphonic acid, acetodiphosphonic acid, and etidronic acid, in solid or powder form (acidic solid HEDP) from the People's Republic of China (China) are circumventing the antidumping duty (AD) and countervailing duty (CVD) orders on HEDP from China.
**DATES:**
Applicable February 23, 2026
**FOR FURTHER INFORMATION CONTACT:**
Charles Vannatta, Office of Policy, Enforcement and Compliance, International Trade Administration, U.S. Department of Commerce, 1401 Constitution Avenue NW, Washington, DC 20230; telephone: (202) 482-4036.
**SUPPLEMENTARY INFORMATION:**
**Background**
On May 9, 2025, Commerce published in the *Federal Register* its *Preliminary Determination*[^1] that imports of acidic solid HEDP produced in China are circumventing the *Orders.*[^2] Commerce conducted this circumvention inquiry pursuant to section 781(c) of the Tariff Act of 1930, as amended (the Act), and 19 CFR 351.226(j). On May 23, 2025, Jiangshan America, LLC (Jiangshan America) and Uniphos, Inc. (Uniphos) (collectively, the U.S. Importers) submitted a case brief. [^3] On May 30, 2025, Compass Chemical International LLC (Compass, a domestic interested party) submitted a rebuttal brief. [^4]
[^1]*See 1-Hydroxyethylidene-1, 1-Diphosphonic Acid from the People's Republic of China: Preliminary Affirmative Determination of Circumvention,* 90 FR 19668 (May 9, 2025) ( *Preliminary Determination* ), and accompanying Preliminary Decision Memorandum (PDM).
[^2]*See 1-Hydroxyethylidene-1, 1-Diphosphonic Acid from the People's Republic of China: Amended Final Determination of Sales at Less Than Fair Value, and Antidumping Duty Order,* 82 FR 22807 (May 18, 2017) ( *AD Order* ); *see also 1-Hydroxyethylidene-1, 1-Diphosphonic Acid from the People's Republic of China: Countervailing Duty Order,* 82 FR 22809 (May 18, 2017) ( *CVD Order* ) (collectively, *Orders* ).
[^3]*See* U.S. Importers' Letter, “Case Brief,” dated May 23, 2025 (U.S. Importers' Case Brief).
[^4]*See* Compass' Letter, “Rebuttal Comments in Response to Comments on the Preliminary Determination,” dated May 30, 2025 (Compass' Rebuttal Comments).
Due to the lapse in appropriations and Federal Government shutdown, on November 14, 2025, Commerce tolled all deadlines in administrative proceedings by 47 days. [^5] Additionally, due to a backlog of documents that were electronically filed via Enforcement and Compliance's Antidumping and Countervailing Duty Centralized Electronic Service System (ACCESS) during the Federal Government shutdown, on November 24, 2025, Commerce tolled all deadlines in administrative proceedings by an additional 21 days. [^6] On December 18, 2025, Commerce extended the deadline for issuing the final determination in this circumvention inquiry by 35 days. [^7] On January 14, 2026, Commerce extended the deadline for issuing the final determination in this circumvention inquiry by an additional 23 days. [^8] Accordingly, the deadline for this final determination is now February 18, 2026.
[^5]*See* Memorandum, “Deadlines Affected by the Shutdown of the Federal Government,” dated November 14, 2025.
[^6]*See* Memorandum, “Tolling of all Case Deadlines,” dated November 24, 2025.
[^7]*See* Memorandum, “Extension of Deadline for the Final Determination in the Circumvention Inquiry,” dated December 18, 2025.
[^8]*See* Memorandum, “Second Extension of Deadline for the Final Determination in the Circumvention Inquiry,” dated January 14, 2026.
For a summary of events that occurred since the *Preliminary Determination,* as well as a full discussion of the issues raised by parties for consideration in the final determination, *see* the Issues and Decision Memorandum. [^9]
[^9]*See* Memorandum, “Issues and Decision Memorandum for the Circumvention Inquiry of the Antidumping and Countervailing Duty Orders on 1-Hydroxyethylidene-1, 1-Diphosphonic Acid from the People's Republic of China,” dated concurrently with, and hereby adopted by, this notice (Issues and Decision Memorandum).
The Issues and Decision Memorandum is a public document and is on file electronically via Enforcement and Compliance's Antidumping and Countervailing Duty Centralized Electronic Service System (ACCESS). All issues raised in this inquiry are addressed in the Issues and Decision Memorandum. A list of the topics discussed in the Issues and Decision Memorandum is attached to this notice at Appendix II. ACCESS is available to registered users at *https://access.trade.gov.* In addition, a complete version of the Issues and Decision Memorandum can be accessed at *https://access.trade.gov/public/FRNoticesListLayout.aspx.*
**Scope of the Orders**
The merchandise covered by the *Orders* includes all grades of aqueous acidic (non-neutralized) concentrations of HEDP from China. For a complete description of the scope of the *Orders, see* Appendix I of this notice.
**Merchandise Subject to the Circumvention Inquiry**
The merchandise subject to the circumvention inquiry (inquiry merchandise) includes all grades of acidic (non-neutralized) concentrations of 1-hydroxyethylidene-1, 1-disphosphonic acid (HEDP), also referred to as hydroxyethylidenendiphosphonic acid, hydroxyethanediphosphonic acid, acetodiphosphonic acid, and etidronic acid, in solid or powder form (acidic solid HEDP), produced in China and exported to the United States. The Chemical Abstract Service (CAS) registry number for acidic solid HEDP is 2809-21-4. The solid or powder form of acidic HEDP subject to this circumvention inquiry is typically entered into the United States under Harmonized Tariff Schedule of the United States (HTSUS) subheadings 2931.49.0080, 2931.90.9052, and 2811.19.6190.
**Analysis of Comments Received**
Based on our analysis of the comments received, we made no changes to the *Preliminary Determination,* as described below, and at the Comment of the Issues and Decision Memorandum.
**Methodology and Final Circumvention Determination**
Commerce conducted this circumvention inquiry in accordance with section 781(c) of the Act and 19 CFR 351.226. For this final determination, Commerce continues to rely on facts available under section 776(a) of the Act, including facts available with adverse inferences (AFA) under section 776(b) of the Act with respect to all known Chinese producers and exporters of acidic solid HEDP, due to their failure to respond to Commerce's requests for information. For further explanation of Commerce's decision to rely on AFA with respect to all known Chinese producers and exporters of acidic solid HEDP, *see* the Issues and Decision Memorandum. As a result, in accordance with section 781(c) of the Act, Commerce determines that the inquiry merchandise produced in and exported from China is circumventing the *Orders.* Furthermore, Commerce is applying this affirmative determination of circumvention of the *Order* s on a country-wide basis.
**Suspension of Liquidation and Cash Deposit Requirements**
Based on the affirmative country-wide determinations of circumvention, in accordance with 19 CFR 351.226(l)(3) and (m)(1)(ii), we will direct CBP to suspend liquidation of all unliquidated entries of acidic solid HEDP produced in and exported from China that were entered, or withdrawn from warehouse, for consumption on or after December 19, 2024, the date of publication of the initiation of this circumvention inquiry in the *Federal Register* . [^10]
[^10]*See 1-Hydroxyethylidene-1, 1-Diphosphonic Acid from the People's Republic of China: Initiation of Circumvention Inquiry of the Antidumping and Countervailing Duty Orders,* 89 FR 103779 (December 19, 2024).
In addition, we will direct CBP to collect a cash deposit for estimated antidumping duties. For exporters of acidic solid HEDP that have a company-specific separate AD cash deposit rate under the *AD Order,* the cash deposit rate will be the exporter-specific or producer/exporter-specific separate AD cash deposit rate established for that company in the most recently completed segment of this proceeding. For exporters of acidic solid HEDP that do not have an exporter-specific or producer/exporter-specific separate AD cash deposit rate, the AD cash deposit rate will be equal to the cash deposit rate for the China-wide entity. [^11]
[^11]*See AD Order,* 82 FR at 22808.
Further, we will direct CBP to collect a cash deposit for estimated countervailing duties. If the acidic solid HEDP was produced and exported by the same company, the cash deposit rate will be equal to the company-specific CVD cash deposit rate established for that company in the most recently completed segment of this proceeding. If both the producer and the exporter of the subject merchandise have company-specific CVD cash deposit rates, and their rates differ, the cash deposit rate will be the higher of these two rates. If either the producer or the exporter, but not both, have company-specific cash deposit rates, the cash deposit rate will be that company's CVD cash deposit rate. For companies that do not have a company-specific CVD cash deposit rate, the CVD cash deposit rate will be the cash deposit rate for all other producers and exporters. [^12]
[^12]*See CVD Order,* 82 FR at 22810.
These suspension of liquidation and cash deposit requirements will remain in effect until further notice.
**Administrative Protective Order**
This notice will serve as the only reminder to all parties subject to an administrative protective order (APO) of their responsibility concerning the destruction of proprietary information disclosed under APO in accordance with 19 CFR 351.305(a)(3). Timely written notification of the return or destruction of APO materials or conversion to judicial protective order is hereby requested. Failure to comply with the regulations and the terms of an APO is a sanctionable violation.
**Notification to Interested Parties**
Commerce is issuing and publishing this determination in accordance with section 781(c) of the Act and 19 CFR 351.226(g)(2).
Dated: February 18, 2026.
Christopher Abbott,
Deputy Assistant Secretary for Policy and Negotiations, performing the non-exclusive functions and duties of the Assistant Secretary for Enforcement and Compliance.
**Appendix I**
**Scope of the Orders**
The merchandise covered by the *Orders* includes all grades of aqueous acidic (non-neutralized) concentrations of 1-hydroxyethylidene-1, 1-disphosphonic acid (HEDP), also referred to as hydroxyethylidenendiphosphonic acid, hydroxyethanediphosphonic acid, acetodiphosphonic acid, and etidronic acid. The Chemical Abstract Service (CAS) registry number for HEDP is 2809-21-4.
The merchandise subject to the *Orders* is currently classified in the Harmonized Tariff Schedule of the United States (HTSUS) at subheading 2931.90.9043. It may also enter under HTSUS subheadings 2811.19.6090, 2931.90.9041, 2931.90.9051, 2811.19.6190, 2931.39.0018, 2931.49.0050 and 2931.49.0080. While HTSUS subheadings and the CAS registry number are provided for convenience and customs purposes only, the written description of the scope of the *Orders* is dispositive.
**Appendix II**
**List of Topics Discussed in the Issues and Decision Memorandum**
I. Summary
II. Background
III. Scope of the *Orders*
IV. Merchandise Subject to the Circumvention Inquiry
V. Period of Circumvention Inquiry
VI. Use of Facts Available and Adverse Inferences
VII. Discussion of the Issue
Comment: Submission of New Factual Information from U.S. Importers
VIII. Recommendation