SK Group Sells Semiconductor Wafer Unit SK Siltronic to Doosan for ₩2.3 Trillion

The Quick Take

• SK Group agreed to sell a 70.6% stake in semiconductor wafer maker SK Siltronic to Doosan Group for ₩2.3 trillion (approximately $1.7 billion).
• The deal marks Doosan's strategic entry into the semiconductor sector, adding to its existing energy and machinery business pillars.
• SK Corp will transfer both its directly held 51% stake and an additional 19.6% held via a total return swap agreement.
• The board of SK Corp approved the transaction at a special meeting on July 31, 2026.

SK Group's divestiture of a 70.6% controlling stake in SK Siltronic, a semiconductor silicon wafer manufacturer, to Doosan Group for ₩2.3 trillion marks a significant reshaping of Korea's industrial conglomerate landscape. SK Siltronic produces silicon wafers — the foundational substrate for semiconductor chips — and the sale places a critical component in Korea's semiconductor supply chain under new ownership. SK Group's strategic rationale appears tied to portfolio rationalization, while Doosan gains a high-margin industrial asset to diversify beyond traditional heavy industries.

The transaction has broad implications for Korea's semiconductor supply chain. SK Hynix and Samsung Electronics, which rely on domestic wafer supply, may face supply chain uncertainty during any ownership transition period. Doosan's expanded semiconductor footprint strengthens its position as an integrated industrial conglomerate, potentially attracting institutional interest. For global wafer market dynamics, the deal puts Siltronic AG of Germany and Shin-Etsu Chemical of Japan on alert regarding any shift in SK Siltronic's customer allocation or pricing strategy under new management.

Watch for Korean Fair Trade Commission (KFTC) and potentially CFIUS-equivalent regulatory review, given the semiconductor sector's strategic sensitivity. The closing timeline and any earnout provisions will determine whether Doosan can integrate Siltronic without disrupting existing supply agreements. The macro variable is semiconductor demand: if AI-driven wafer demand accelerates through 2026-2027, Doosan may have acquired a high-value asset at a favorable point in the cycle, while SK Group risks selling at an inflection point in wafer pricing recovery.

Synthesized from 4 sources.