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  1. AD/CVD Catalog
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  5. CSMS 64330423
CSMS 64330423·Trade policy·March 6, 2025·View on csms.cbp.gov ↗

Initiation of Antidumping Duty Investigations: Methylene Diphenyl Dissocyanate from the People’s Republic of China

Plain-English explanation

CSMS 64330423 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (trade policy), published on March 6, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "Initiation of Antidumping Duty Investigations: Methylene Diphenyl Dissocyanate from the People’s Republic of China". CSMS messages are the operational layer between Commerce determinations and at-the-border collections: when Commerce publishes a new rate, scope ruling, or instruction, CBP turns it into a CSMS that ACE/ACS systems and brokers act on.

Message body

Full text as published by U.S. Customs and Border Protection

CSMS # 64330423 - Initiation of Antidumping Duty Investigations: Methylene Diphenyl Dissocyanate from the People’s Republic of China U.S. Customs and Border Protection sent this bulletin at 03/06/2025 12:04 PM EST   Cargo Systems Messaging Service CSMS # 64330423 - Initiation of Antidumping Duty Investigations: Methylene Diphenyl Dissocyanate from the People’s Republic of China On March 4, 2025, the Department of Commerce (Commerce) initiated its less-than-fair-value duty investigation on “Methylene Diphenyl Dissocyanate from the People’s Republic of China” (Initiation Notice). This investigation has been assigned the following case number: A-570-200. The Scope of Merchandise covered by this investigation reads as follows : The merchandise subject to this investigation is methylene diphenyl diisocyanate (MDI), which is an aromatic polyisocyanate material whose composition includes two or more isocyanate groups (i.e., functional group containing a nitrogen atom, a carbon atom, and an oxygen atom bonded together (-NCO)) attached to one or more benzene rings (i.e., flat, symmetrical molecule made up of six carbon atoms arranged in a hexagonal ring and has the chemical formula C6H6) that are joined by methylene bridges (i.e., a carbon atom bound to two hydrogen atoms (−CH2−) and connected by single bonds to two other distinct atoms in the rest of the molecule). MDI is commonly called Polymeric, Monomeric, or Modified MDI and may also be referred to under other names, including Methylene bisphenyl isocyanate, 4,4’-Diphenylmethane diisocyanate, Methylene di-p-phenylene ester of isocyanic acid, Methylene bis(4-phenyl isocyanate), and polymethylene polyphenylene isocyanate. MDI is normally associated with Chemical Abstracts Service (CAS) registry numbers 9016-87-9, 101-68-8, 5873-54-1, 2536-05-2, 1689576-89-3, 25686-28-6, 26447- 40-5, and 39310-05-9, but several others are also used. MDI ranges in physical form from low viscosity liquids to solids.  MDI is covered by the scope of this investigation irrespective of whether it has gone through a distillation process and regardless of acid content, reactivity, functionality, freeze stability, physical form, viscosity, grade, purity, molecular weight, or packaging. MDI may contain additives, such as catalysts, solvents, plasticizers, antioxidants, fire retardants, colorants, pigments, diluents, thickeners, fillers, softeners, toughening agents. The scope does not include mixtures of MDI with other materials, when the combined MDI component comprises less than 40 percent of the total weight of the mixture. MDI may be partially reacted with itself, polyol, or polyamines, and retain MDI component that has not fully chemically reacted so as to convert it into a different product no longer containing isocyanate groups. These products are known as homopolymer, uretonimine MDI, carbodiimide MDI, or prepolymers.  The scope does not include partially reacted MDI when its NCO content is less than 10 weight percentage. For MDI that enter as part of a system with separately packaged resin consisting mostly of a chemical compound that has an OH reactive group, including polyol, only the MDI portion of the system is included in the scope.  The scope does not include any separately packaged polyol that would not fall within the scope if entered on its own. The scope includes merchandise matching the above description that has been processed in a third country, including by commingling, diluting, introducing or removing additives, or performing any other processing that would not otherwise remove the merchandise from the scope of the investigation if performed in the subject country. The scope also includes MDI that is commingled or blended with MDI from sources not subject to this investigation. Only the subject component of such commingled products is covered by the scope of this investigation. This merchandise is currently classifiable under Harmonized Tariff Schedule of the United States (HTSUS) subheadings 2929.10.8010 and 3909.31.0000.  Subject merchandise may also be entered under subheadings 3824.99.2600, 3909.50.1000, 3909.50.2000, 3909.50.5000, 3824.99.2900, 3506.91.5000, 3911.90.4500, 3921.13.5000, and 3920.99.5000. The HTSUS subheadings are provided for convenience and customs purposes only; the written description of the scope is dispositive. Parties may submit comments on the scope of the investigations. Please be sure to comply with all requirements pertaining submitting comments as described in the forthcoming Initiation Notice. Upon their publication in the Federal Register, the Initiation Notice may be found at www.federalregister.gov via the search bar using the case number assigned to this investigation. Importers should be aware that entries of subject merchandise made after the initiation of an investigation may retroactively be subject to antidumping duties. For questions about CBP’s AD/CVD enforcement, see Priority Trade Issue: Antidumping and Countervailing Duties | U.S. Customs and Border Protection (cbp.gov) .   Update your subscriptions, modify your password or e-mail address, or stop subscriptions at any time on your Subscriber Preferences Page . You will need to use your e-mail address to log in. If you have questions or problems with the subscription service, please contact subscriberhelp.govdelivery.com . This service is provided to you at no charge by U.S. Customs and Border Protection . Privacy Policy | GovDelivery is providing this information on behalf of U.S. Department of Homeland Security, and may not use the information for any other purposes. Powered by Privacy Policy | Cookie Statement | Help

Frequently asked questions

What is CSMS 64330423?

CSMS 64330423 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "Initiation of Antidumping Duty Investigations: Methylene Diphenyl Dissocyanate from the People’s Republic of China". CSMS bulletins are the operational instructions CBP issues to brokers, importers, and ACE filers covering rate changes, system updates, scope guidance, and other day-to-day customs-operations changes.

When was CSMS 64330423 published?

CBP published CSMS 64330423 on March 6, 2025. The bulletin's instructions are typically operative as of the publication date unless the body specifies a different effective date.

Is the CBP CSMS the legally binding instruction?

Yes — for at-the-border filing and entry collection. CSMS messages translate Commerce's Federal Register determinations into operational CBP instructions that ACE/ACS systems and brokers execute. The Federal Register notice is the underlying legal authority; the CSMS is the operational implementation. Both should be read together when reconciling a rate or scope change.

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