Even as the U.S. Department of the Treasury has released its proposed regulations beefing up national security reviews by the Committee on Foreign Investment in the U.S., the interagency panel chaired by the department, some CFIUS lawyers are voicing concern that the Commerce Department has yet to release its own set of draft rules defining "emerging and foundational technologies," which are included in critical technologies under the new law.

Some worry that the Commerce Department's delay in establishing the definitions is allowing many venture capital and joint investments by foreign entities in emerging technologies, such as artificial intelligence and robotics, to continue apace without a CFIUS review because they are not subject to controls under critical technologies, even as the Treasury and other agencies on the panel continue working toward the February 2020 deadline for final regulations. The uncertainty caused by the delay is causing anxiety for some clients, they said.

"There are still an enormous amount of technology companies and activities that are outside the reach of CFIUS because the Commerce Department has not yet moved with any speed to define the terms emerging and foundational technologies," said Giovanna Cinelli, a partner and international trade and national security practice leader at Morgan, Lewis & Bockius in Washington, D.C.