The Tokyo District Prosecutor’s Special Investigation Department, alongside the Japan Fair Trade Commission, carried out searches on two oil companies, Higashi Nihon Usami and Kōei Petroleum, for suspected violations of the Antimonopoly Act regarding collusion in diesel pricing. They are investigating claims that multiple firms conspired to set diesel prices for transportation and construction businesses, potentially avoiding competition. Furthermore, other companies, including ENEOS Wing and Enecflit, are also under scrutiny as part of this probe.

According to sources, representatives from the eight companies involved are accused of discussing and deciding on diesel prices sold to businesses operating out of Tokyo to avoid competition. These firms are reported to account for over half the market share in this sector. The investigation follows a significant rise in diesel prices, which increased by approximately 1.5 times since May 2020, leading to concerns that such collusion may have contributed to the prolonged high pricing of diesel fuel.

Additionally, the increasing fuel costs are expected to impact the prices of goods and services as well as the costs of public works and housing projects, potentially affecting the daily lives of citizens. The outcomes of this investigation could have substantial implications for market competition in the energy sector and overall economic conditions in Japan.