Lee Sang-hoon, chairman of Samsung Electronics, was sentenced to 18 months in prison for preventing union customer service staff.

The central district court in Seoul on December 17 accused Lee Sang-hoon and vice president Kang Kyung-hoon of violating union laws. Prosecutors said that in 2013, they ordered subordinates to cut union members' salaries, digging for private information about them such as pregnancy and debt.

Lee was then the chief financial officer of Samsung Electronics, and both Mr. Kang and Mr. Lee were members of the Office of the Future Strategy - the important decision-making department that had been disbanded. Kang also received 18 months in prison just like Lee.

Lee denied the allegations but Samsung Electronics declined to comment on whether the two leaders will appeal.

Samsung Electronics, the leading subsidiary of Samsung Group, is the world's largest manufacturer of phones and chips. Lee Sang-hoon became president of the company in March.