17th June 2025 – (Tokyo) A man from Hong Kong used his own “winning algorithm” to gamble in Japan and win billions of yen, taking advantage of special tax rules for non-residents that kept him out of legal trouble. Japanese news reports indicate that this individual developed a unique computer program more than ten years ago. He brought in two helpers, Tani Tsuyoshi and Tokunaka Tōryō, to help with the job. These two individuals used the names of 60 friends and family members to set up betting accounts and placed over 100 bets for every competition.

During 2019 and 2021, they reportedly generated profits exceeding ¥6.1 billion (approximately HK$33 million) by betting on horse races, local sports, and boat races. However, ¥2.6 billion (roughly HK$14 million) of this income was not reported for tax purposes, and as a result, Tokyo tax officers filed charges against them based on Japan’s income tax regulations. One of the men, Tani, was once the boss of a J3 football club management company, while Tokunaka was a top manager in a restaurant business. Later, they corrected their tax documents and paid what they owed. They apologised and shared, “We deeply regret the inconvenience caused.”

Hong Kong Mastermind Escapes Charges in Billion-Yen Japanese Gambling Scheme

The main person from Hong Kong still faces no charges, because Japanese tax rules do not apply to his earnings. According to reports, he retained 90% of the money, earning billions of yen, and left just 10% for his assistants. Their advanced setup, utilizing an automated computer system, enabled them to purchase numerous betting slips online, with monthly bets sometimes reaching ¥2 billion (approximately HK$109 million). Although they saw steady profits each month, the project broke down after a 2024 probe by Japan’s National Tax Agency spotted suspicious patterns in the assistants’ reports.
Japanese officials have not taken more steps against the Hong Kong mastermind, who is still free and enjoying the benefits of his expertly built gambling system.