The representative director of Koyama Suido Kensetsu, in relation to the company's operations, on October 18, 2023, at a water pipe replacement construction site located between 5-12 Minami-Naruse, Machida City, Tokyo, and 6-12 Minami-Naruse, Machida City, during asphalt accumulation work on a dump truck bed, a worker fell from the truck bed to the ground, sustaining injuries including traumatic cervical syndrome, and was absent for more than four days. The company and its representative failed to submit the worker injury report to the Hachioji Labor Standards Inspection Office Machida Branch without delay, until June 18, 2024, thereby failing to report as required by law. Consequently, they were sentenced to a fine of 200,000 yen for violating the Industrial Safety and Health Act, as confirmed by the Machida Summary Court on July 25, 2025. This violation corresponds to Article 28, Paragraph 1, Item 3 of the Construction Business Act.