A bipartisan group of U.S. lawmakers has raised national security concerns about Intel's testing of chipmaking tools from ACM Research, a California-based equipment maker with deep Chinese ties. Senators Elizabeth Warren and Tom Cotton led the effort, questioning whether ACM could transfer sensitive information from Intel's facilities to Chinese military-linked companies.

The lawmakers specifically cited ACM's connections to sanctioned Chinese firms including YMTC, CXMT, and SMIC. In a letter to Intel CEO Lip-Bu Tan, they warned that ACM's presence in Intel's facilities could expose cutting-edge chipmaking processes. Intel responded that ACM tools are not used in its semiconductor production and that the company fully complies with U.S. laws and regulations.

This scrutiny comes as Intel faces additional pressure from its partial government ownership stake, which lawmakers say creates unique fiduciary responsibilities. The House Select Committee on China previously expressed concern about ACM selling equipment to U.S. manufacturers. The bipartisan nature of the letter, signed by both Democratic and Republican lawmakers, underscores the growing consensus about China's role in American semiconductor manufacturing and the need for heightened security measures.