Seoul prosecutors estimate 16 trillion won of collusion across seven Korean petrochemical makers

Sixteen trillion won is prosecutors' estimate of the scale of the alleged collusion, and it is the largest figure in a case the prosecution service has investigated directly ^[1]. Whether it counts the sales the cartel touched or the overcharge on those sales changes the liability by a wide margin. The report does not say how the figure was built, and it includes no fine, charging decision or response from any of the seven companies ^[16].

Prosecutors asked the court to detain all eight of the current and former executives and employees they had questioned, and came away with two, both at PKC, or a quarter of what they sought ^[3][5][13]. The court cited the scale of the alleged collusion, the gravity of the offense and the risk that evidence would be destroyed ^[4]. The other six included OCI vice chairman and chief executive Kim Yoo-shin and former PKC chief executive Jang Young-soo. The court said they should be allowed to defend themselves without being detained ^[5]. Only one of the seven companies named has an employee in custody ^[14].

The April overlap is the part hardest to argue around. The government began covering 50% of the increase in import prices that month, a measure aimed at naphtha costs driven up by the Iran war and at the inflation worry that came with it. Prosecutors found the collusion continued after it started ^[6][7]. The investigation team concluded the companies kept fixing prices to maximize profits while benefiting from that subsidy program ^[8]. Prosecutors also found that when a lawmaker's office asked in 2024 about suspected collusion in caustic soda, officials at one large chemical company answered with false information in a coordinated manner. The collusion continued afterward, according to legal sources cited by Seoul Economic Daily ^[9].

The office running the case is being abolished in October. The grace and transition period for unresolved cases and the transfer of supplementary investigations runs through the end of the year ^[10]. The overlapping authority runs three months at the outside ^[15]. "Even with the abolition of the prosecution service close at hand, investigations into price-fixing cases are continuing," a legal source said ^[11]. The same source added: "After prosecutors handled more than a dozen antitrust cases from last year through this year, it will also be worth watching what results the Major Crimes Investigation Agency produces in antitrust enforcement right after its launch" ^[12].

The 16 trillion won could describe commerce touched, the eventual penalty a small fraction of it, the earnings effect landing in a footnote. Or the file survives the handover, and the April subsidy overlap and the 2024 answers to the lawmaker's office push it toward the harsh end ^[6][9]. Or the transfer absorbs the momentum and the estimate never becomes a charge. I would expect the middle one, on the strength of the stated plan to examine the remaining allegations through year end ^[10]. A charging document that scopes the figure down to a much smaller base would break that view, and so would a transfer that separates the case from the team that built it.

Meanwhile all seven companies have executive and legal time committed to this through at least the transition period ^[2][10]. The naphtha cost problem the subsidy was written to ease gets none of that attention ^[7].