SK Group Chairman Chey Tae-won announced he would appeal a record $1 billion (1.38 trillion won) divorce settlement with his estranged wife, Roh So-young, to South Korea’s Supreme Court. Chey claimed a “critical error” in the appellate court’s calculation of Roh’s contribution to SK Group’s growth, arguing that the court incorrectly valued Korea Telecom shares, inflating asset values before and after Chey inherited the company.

SK Group, the parent company of SK Hynix, is one of the world’s key semiconductor manufacturers. Chey has recently sought to collaborate with TSMC, ASML and Nvidia to enhance SK Group’s competitive position.