TULSA, Okla. (KFOR) – A 35-year-old Chinese national, who is a legal US resident in Oklahoma, pleaded guilty Tuesday in federal court to committing theft of trade secrets from his employer, a US petroleum company.

Hongjin Tan pleaded guilty to theft of a trade secret, unauthorized transmission of a trade secret, and unauthorized possession of a trade secret.

U.S. Attorney’s Office for the Northern District of Oklahoma says Tan stole the information from a U.S.-based petroleum company regarding the manufacturing of a “research and development downstream energy market product” that is worth more than $1 billion.

“China’s economic aggression poses a threat to America’s emerging high-technology industries. Industrial spies like Hongjin Tan engage in espionage to steal American trade secrets and intellectual property born out of the innovation that is innate in our free market system,” said U.S. Attorney Trent Shores for the Northern District of Oklahoma. “Thanks to a vigilant company and the investigative efforts of the FBI, Hongjin Tan was caught red-handed and prosecuted. American ingenuity and know-how are the envy of the international market, and the U.S. Attorneys community will work to protect our economic infrastructure.”

Tan was employed as an associate scientist for the U.S. petroleum company from June 2017 until December 2018. He was working within a group at the company with the goal of developing next-generation battery technologies for stationary energy storage.

In his plea agreement, Tan admitted to intentionally copying and downloading research and development materials without authorization.

“Trade secret theft is a serious crime which hurts American businesses and taxpayers. The FBI will continue to protect our country’s industries from adversaries who attempt to steal valuable research and technology,” said FBI Special Agent in Charge Melissa Godbold of the Oklahoma City Field Office.

On Dec. 11, 2018, Tan used a thumb drive to copy hundreds of files. He subsequently turned in his resignation and was escorted from the premises on Dec. 12, 2018. Later that day, he returned the thumb drive, claiming that he had forgotten to do so before leaving.

Upon examination, they discovered that there were five documents that had been deleted.

Investigators with the FBI searched and found an external hard drive. They discovered that the same five missing files from the thumb drive had been downloaded to the hard drive.

Tan maintained the files on a hard drive so he could access the data at a later date.

“Tan’s guilty plea continues to fill in the picture of China’s theft of American intellectual property,” said Assistant Attorney General for National Security John C. Demers. “The Department launched its China Initiative to battle precisely the type of behavior reflected in today’s plea—illegal behavior that costs Americans their jobs–and we will continue to do so.”

U.S. District Judge Gregory K. Frizzell presided over the plea hearing and set sentencing for Feb. 12, 2020.