A Tokyo Summary Court ruled on Wednesday that advertising giant Dentsu Inc. will stand trial for alleged labor practice violations, a decision that is sure to sound alarm bells at many of the nation's companies, especially with the recent public backlash against cases of karoshi, or death by overwork, experts say.

Prosecutors had moved to seek a summary court order for Dentsu to pay fines based on simplified criminal proceedings, called a summary indictment. A summary order, which would be issued without an open trial, is for this case "inadequate," according to the court

Dentsu was summarily indicted on July 5, but the prosecutors stopped short of indicting senior Dentsu officials for allegedly making employees work illegally long hours, as prosecutors believed that the actions by firm managers were not enough to merit such punishment.