October 17, 2022: -ASML, one of the planet’s most essential semiconductor toolmakers, told U.S. employees to control servicing Chinese customers as Washington’s latest export restrictions hit the global chip industry.

The Dutch company said in a note that any U.S. staff, which include American citizens, green card holders, and western nationals living in the U.S., “are prohibited from providing specific services to advanced fabs in China.”

ASML’s U.S. employees “must refrain directly or indirectly from servicing, shipping, or providing support for any customers in China until further notice, while ASML sets which particular fabs are affected by this condition.” A fab is another name for a chip manufacturing plant.

The ASML memo, circulating on social media, was confirmed as authentic by a spokesperson for the company.

ASML is one of the essential players in the semiconductor supply chain as it produces a machine needed to make the most advanced chips in the world. The Netherlands-headquartered company is the only company that makes these powerful ultraviolet lithography machines, which are used by the likes of TSMC, the most advanced chip manufacturer in the world.

The previous week, the U.S. government enacted sweeping rules to cut China off from key chips and semiconductor manufacturing equipment.

As part of those rules, “U.S. persons” that support the development or production of specific chips in China, including those for military use, require a charge.

The rule appears quite wide-ranging, and companies are scrambling to figure release what it means in practice.

“We are working diligently to evaluate the regulations and their impact on ASML,” the company added in its memo.

Meanwhile, the U.S. has granted exemptions from its new curbs to some of the largest chipmakers in the world.

TSMC has obtained a one-year license to continue purchasing American chipmaking equipment and send it to its manufacturing facility in China, the Nikkei said on Friday. TSMC’s functions at its Nanjing, China, plant are for small refined chips.

Washington is particularly concerned regarding China obtaining access to the most developed chips that can be used in military applications, artificial intelligence, or supercomputing.