Samsung Electronics is trading at KRW 270,000, down 5.43%, as the stock went ex-dividend today, September 29, 2026, meaning new buyers are no longer eligible for the quarterly payout. The company's shares typically adjust to reflect the value of the dividend on the ex-dividend date. Broader market sentiment also contributed, with rising U.S. Treasury yields pressuring chip stocks, including peer SK hynix which fell 5.05%. Concerns about AI-chip demand and geopolitical tensions also added to semiconductor weakness.