Japanese advertising giant Dentsu Inc. said Tuesday it will pay about 2.4 billion yen ($22 million) to its employees next month in unpaid overtime for the two years up to March 2017 following its conviction of labor practice violations.

Some workers at Dentsu refrained from reporting overtime hours when they were checking data or doing other office work beyond their regular hours, regarding the extra hours as "self-improvement" activities, the company said.

Dentsu began encouraging its workers to report their unpaid overtime hours after labor inspectors ordered the company to scrutinize their working hours and conditions.

In October, the ad agency was ordered by a court to pay 500,000 yen for labor practice violations, which resulted in the 2015 suicide of a new female recruit due to excessive overtime work.

The company's practice that led to the death of 24-year-old Matsuri Takahashi sparked a national debate over severe working conditions in Japan and prodded the government and business circles to start improving working environments.

In its earnings report for the January-September period, Dentsu earmarked some 2.37 billion yen for "lump sum payments related to working hours."

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