South Korea indicts four oil refiners for alleged price collusion

South Korean prosecutors have indicted the nation's four largest oil refiners on suspicion of colluding to fix fuel prices, a move that allegedly caused billions of dollars in anti-competitive harm. The companies named in the indictment are HD Hyundai Oilbank, SK Energy, GS Caltex, and S-Oil.

The Seoul Central District Prosecutors’ Office alleges that pricing managers at HD Hyundai Oilbank and SK Energy coordinated on price increases for petroleum products shortly after a conflict erupted in Iran in early 2026. Yonhap News Agency reported that these discussions involved the timing and scale of price hikes.

GS Caltex and S-Oil are also reported to have followed the pricing strategies set by the other two companies. Prosecutors estimate the total anti-competitive effect of this alleged collusion to be around 26 trillion won, equivalent to approximately S$22 billion. Representatives from SK Innovation, S-Oil, HD Hyundai Oilbank, and GS Caltex either declined to comment or did not immediately respond to requests for confirmation.

This development comes as South Korea's antitrust regulator, the Korea Fair Trade Commission, recently increased penalties for collusion. The maximum penalty is now at least 10 percent of sales related to the violation, a significant rise from the previous minimum of 0.5 percent.