https://www.siliconvalley.com/2021/01/15/h-1b-homeland-securitys-ice-develops-new-unit-to-probe-opt-foreign-student-work-permit/

The U.S. Department of Homeland Security is developing a new unit to probe use of the Optional Practical Training work permit for foreign students, and to recommend investigations of students and employers.

The OPT program, widely used in the Silicon Valley technology industry and often a pathway to the H-1B visa intended for jobs requiring specialized skills, allows foreign students to work in the U.S. for up to three years.