The Tokyo District Court on Tuesday ordered a steak restaurant chain and two company personnel to pay ¥57.9 million in damages to the parents of an employee who killed himself due to overwork and harassment.

The court determined there was no comparable negligence on the part of the young employee to offset the damages, an unusual ruling for a suit seeking damages for a suicide, a lawyer for the plaintiff said.

"The absence of offsetting comparative negligence represents an epoch-making decision," the lawyer said. "This is a ruling that encourages workers suffering from prolonged work and power harassment."

The ruling said the man, who began working for Tokyo-based Sun Challenge in 2007 and was appointed to manage a restaurant in 2009, hung himself in November 2010 at age 24 after working extremely long hours over seven months and suffering violence at the hands of a supervisor and insults. He worked an average of 190 hours a month of overtime over the seven months before killing himself, the court found.

"With only one holiday given to him every several months, the psychological load of prolonged work and power harassment caused his mental disorder," said presiding Judge Akira Yamada.

A local labor standards inspection office recognized the suicide as a work-related death in 2012, prompting the man's parents to file a lawsuit against the company, its president and the former supervisor, seeking ¥73 million in damages.