US revokes citizenship of couple convicted of stealing medical secrets and sending them to China

A federal judge revoked the American citizenship of a Chinese-born couple after determining they obtained it illegally after being convicted of conspiring to steal medical trade secrets and share them with China-linked entities, according to a Department of Justice (DOJ) report.

Judicial decision and legal grounds

The ruling was issued on March 30 by Judge James E. Simmons Jr. of the Southern District Court of California, who ordered the denaturalization of Li Chen and Yu Zhou.

According to the court, both had engaged in crimes involving "moral turpitude," which made them ineligible for U.S. citizenship. The decision stresses that naturalization requires a showing of good moral character, a requirement that, according to the ruling, was not met in this case.

Previous convictions for commercial espionage

Chen and Zhou had previously pleaded guilty to conspiracy to commit theft of trade secrets and electronic fraud.

According to the Justice Department, the events occurred during their work as researchers at Nationwide Children's Hospital (NCH), where they specialized in the isolation of exosomes, a technique with medical applications.

The indictment alleges that the pair used confidential information to benefit financially, creating a company of their own and participating in another that exploited stolen secrets.

In addition, the two received funding from a Chinese government entity, the State Administration of Foreign Experts Affairs. Together, they obtained about $1.5 million linked to the transfer of intellectual property, according to the official statement.

Following criminal proceedings, Chen was sentenced to 30 months in prison and Zhou to 33 months, in addition to three years' probation and the joint payment of more than $2.6 million in restitution.

Immigration history

Chen entered the United States in 2007 on an H-1B visa for skilled workers, while Zhou initially did so in 2005 as an exchange visitor and later also obtained an H-1B visa.

Both achieved permanent residency in 2011 and naturalized years later, Chen in 2016 and Zhou in 2017.

However, the court concluded that they had already engaged in unlawful conduct that affected their eligibility before completing the naturalization process.

Investigation and prosecution: The implications

The case was investigated by ICE's Office of Homeland Security Investigations (HSI) and the Office of Chief Counsel (OPLA).

The civil denaturalization proceedings were handled by the Civil Division of the Department of Justice, while the original criminal case was prosecuted by the U.S. Attorney's Office for the Southern District of Ohio.

The decision reinforces the use of denaturalization as a legal tool in serious cases, especially those involving national security and sensitive technology transfer.

It also highlights the growing scrutiny over intellectual property protection in strategic sectors such as medical research, against a backdrop of geopolitical tensions between the United States and China.