Sharp Corporation, which produces iPhone sensors, moved the production of these sensors from its Japanese plant to China. Following this shift, Sharp terminated the contracts of around 3,000 foreign workers. The firm’s hiring is completed by subcontractors. This allows Sharp to end contractual relations with employees whenever it is convenient for the firm, thus putting workers at a disadvantage.
See "Sharp shifted some production to China before nearly 3,000 foreign job cuts", Japan Today, December 5, 2018