United Microelectronics Corp., the Taiwanese semiconductor maker charged with conspiring to steal trade secrets from a U.S. rival, Micron Technology, has brought on the former head of the U.S. Department of Justice Criminal Division to handle the case.

Former Assistant Attorney General Leslie Caldwell, now a partner at Latham & Watkins, made an appearance for UMC on the docket Monday. UMC's co-defendant, Fujian Jinhua Integrated Circuit Co. Ltd., meanwhile, has brought on DOJ veteran Christine Wong, who recently joined Morrison & Foerster after a stint in-house at Fujitsu Ltd.

Defense counsel have yet to make an appearance for three Taiwan nationals also charged in the indictment alongside UMC and Jinhua.

Caldwell and Wong didn't immediately respond to requests for comment Tuesday. Their clients are set to appear for their arraignment Jan. 9, 2019.

Federal prosecutors claim that UMC partnered with Jinhua, a state-owned Chinese enterprise, to steal trade secrets of dynamic random-access memory, or DRAM, from Micron. According to the indictment, Micron currently controls between about 20 to 25 percent of market share for DRAM, a technology widely used in digital electronics that require low-cost, high-capacity memory.

According to the indictment, Jinhua was established in early 2016 with $5.65 billion in funding from the Chinese government and affiliated entities for the express purpose of developing and making DRAM. Early that year, the DOJ claims UMC entered a technology cooperation agreement with Jinhua to develop DRAM technology.

Prosecutors claim that two of the individual defendants who were former Micron employees brought trade secrets related to DRAM with them upon taking jobs at UMC. The government claims that one of them downloaded over 900 proprietary Micron files before leaving the company and stored them on USB drives or in the cloud storage where he could access them upon leaving.