CSMS 5118401·Trade policy·April 28, 2025·View on csms.cbp.gov ↗

Initiation of antidumping duty investigation of certain monomers and oligomers from the Republic of Korea (A-580-921)

Plain-English explanation

CSMS 5118401 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (trade policy), published on April 28, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "Initiation of antidumping duty investigation of certain monomers and oligomers from the Republic of Korea (A-580-921)". It links to 1 AD/CVD case in Tandom's catalog. 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.

Linked AD/CVD cases(1)

Cases referenced or affected by this CSMS message

A-580-921

Message body

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

1. On 04/23/2025, Commerce published in the Federal Register its initiation of the antidumping duty investigation of certain monomers and oligomers from the Republic of Korea (90 FR 17044). The effective date of this initiation is 04/16/2025. 2. The products subject to these investigations are certain multifunctional acrylate and methacrylate monomers, and acrylated bisphenol-A epoxy based oligomers (collectively, certain monomers and oligomers or CMOs) that are derived from chemical reactions involving the use of acrylic or methacrylic acid. Products within the scope are listed below and have the following Chemical Abstracts Service (CAS) numbers: 109-16-0 Triethylene glycol dimethacrylate (TEGDMA) C 14 H 22 O 6 . 13048-33-4 1,6-hexanediol diacrylate (HDDA) C 12 H 18 O 4 . 42978-66-5 Tripropylene glycol diacrylate (TPGDA) C 15 H 24 O 6 . 3290-92-4 Trimethylolpropane trimethacrylate (TMPTMA) C 18 H 26 O 6 . 15625-89-5 Trimethylolpropane triacrylate (TMPTA) C 15 H 20 O 6 . 28961-43-5 Ethoxylated trimethylol-propane triacrylate (EOTMPTA) (C 2 H 4 O) n (C 2 H 4 O) n (C 2 H 4 O) n C 15 H 20 O 6 . 57472-68-1 Dipropylene glycol diacrylate (DPGDA) C 12 H 18 O 5 . 55818-57-0 Bisphenol-A-epichlorohydrin copolymer acrylate (EPOXY ACRYLATE) (C 15 H 16 O 2 -C 3 H 5 ClO) x -xC 3 H 4 O 2 . The monomers are generally known as multifunctional acrylates (MFAs) or multifunctional methacrylates (MFMAs) depending on whether the functional groups are acrylate or methacrylate. The monomers generally contain stabilizers/inhibitors, which include but are not limited to Hydroquinone, Methyl Hydroquinone, and Butylated Hydroxy Toluene. The monomers are either difunctional or trifunctional (having 2 or 3 functional groups/molecule), have viscosities of 9 to 15 centipoise (cPs) at 25 degrees Celsius (if difunctional) or 44 to 110 cPs at 25 degrees Celsius (if trifunctional), have (meth)acrylate equivalent weights (molecular weight per number of functional groups) between 99 and 158 and molecular weights between 226 and 472 grams per mol. The acrylated bisphenol-A epoxy based oligomer is commonly referred to as epoxy acrylate or acrylated epoxy. In contrast to epoxy resin, the main characteristic of the epoxy acrylate oligomer is that it contains acrylate functional groups which make them curable by free-radical polymerization. The epoxy acrylate has a molecular weight between 508 to 536 grams per mol and a viscosity of 2400 to 3600 cPs at 65 degrees Celsius. The epoxy acrylate generally contains stabilizers/inhibitors, which include but are not limited to Hydroquinone, Methyl Hydroquinone, and Butylated Hydroxy Toluene. Certain monomers and oligomers are subject to the scope even if an in-scope monomer or oligomer is blended or mixed with one or more other in-scope monomers or oligomers. Certain monomers and oligomers in any blend or mixture are also subject to the scope, so long as the blend or mixture contains no less than 20 percent by weight of in-scope CMOs. The scope includes merchandise matching the above description that has been processed in a third country, including by commingling, diluting, introducing, or removing ingredients, or performing any other processing that would not otherwise remove the merchandise from the scope of the investigations if performed in the subject country. The scope also includes CMOs that are commingled, mixed or blended with in-scope product from sources not subject to these investigations. Only the subject component(s) of such blends, mixtures or commingled products described above is covered by the scope of these investigations. Subject merchandise contained in a blended, mixed or commingled product described above will not have undergone a chemical reaction as a result of being blended, mixed or commingled. Notwithstanding the above, specifically excluded from the scope are downstream products, including but not limited to, inks, coatings and overprint varnishes. For purposes of this exclusion, the downstream product requires only the application of energy to be cured, e.g., inks or varnish applied to packaging, coatings applied to wood flooring, etc. The energy source required to cure the downstream product to its substrate can be thermal, ultraviolet radiation, visible light, electron beam radiation, or infrared radiation. This merchandise is currently classifiable under Harmonized Tariff Schedule of the United States (HTSUS) subheadings 2916.12.5050, 2916.14.2050, 3824.99.2900, 3907.29.0000 and 3907.30.0000. Subject merchandise may also be entered under subheadings 2916.12.1000 and 3824.99.9397. The HTSUS subheadings and CAS registry numbers are provided for convenience and customs purposes only; the written description of the scope is dispositive. 3. This proceeding has been assigned case number A-580-921. 4. If there are any questions by the importing public regarding this message, please contact the Call Center for the Office of AD/CVD Operations, Enforcement and Compliance, International Trade Administration, U.S. Department of Commerce at (202) 482-0984. CBP ports should submit their inquiries through authorized CBP channels only. (This message was generated by OV:PS/SC.) 5. There are no restrictions on the release of this information. Alexander Amdur

Frequently asked questions

What is CSMS 5118401?

CSMS 5118401 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "Initiation of antidumping duty investigation of certain monomers and oligomers from the Republic of Korea (A-580-921)". 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 5118401 published?

CBP published CSMS 5118401 on April 28, 2025. The bulletin's instructions are typically operative as of the publication date unless the body specifies a different effective date.

Which AD/CVD cases does CSMS 5118401 affect?

CSMS 5118401 references 1 AD/CVD case (A-580-921). The links on this page take you to each linked order with its current scope, rates, and history.

Is the CBP CSMS the legally binding instruction?

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