Sen. Cotton Urges U.S. Restrictions on Chinese Memory-Chip Maker CXMT

Sen. Tom Cotton is urging the Commerce Department to impose tighter restrictions on Chinese memory-chip maker ChangXin Memory Technologies, warning that its expansion could threaten U.S. economic and military advantages.

In a letter sent Thursday to Commerce Secretary Howard Lutnick and first obtained by CNBC, the Arkansas Republican asked the department to add the company, known as CXMT, to the Bureau of Industry and Security's Entity List. Such a designation would restrict its access to U.S. technology and make it harder for American companies to do business with it.

Cotton's request is not itself a new restriction. It asks the administration to take action against a company that has become a larger player in the global market for dynamic random-access memory, or DRAM, used in computers and smartphones.

CXMT is the world's fourth-largest DRAM producer, CNBC reported. Its share of the market by revenue grew from 4% in the second quarter of 2025 to 10% in the same quarter of 2026, according to Counterpoint figures cited by the outlet.

The company is also trying to enter the market for high-bandwidth memory, or HBM, which is used in advanced AI chips. Samsung, SK Hynix and Micron are the main suppliers of that memory. Cotton argued that more should be done to cut CXMT off from the financial and technological resources supporting its growth.

CXMT is already on a Pentagon list of Chinese companies with military ties. That designation is different from the Commerce Department's Entity List and does not carry the same restrictions on U.S. business, according to a technology researcher interviewed by CNBC.

The dispute comes as demand for memory rises with the expansion of AI data centers. Cotton's letter focuses on the risk that wider use of CXMT products could help China increase chip production and advance its high-bandwidth-memory capabilities.