Foreign investors net-sold 11.9465 trillion Korean won in domestic stocks during September 9–16, led by heavy selling of semiconductor shares including SK Hynix and Samsung Electronics. Their purchases shifted toward oil refining, aviation and financial stocks, which are seen as beneficiaries of sustained high oil prices and a strong Korean won. Individual investors took the opposite position, concentrating their buying on Samsung Electronics and other semiconductor-related shares. Brent crude futures for November traded between $105 and $110 a barrel, while the won-dollar exchange rate ranged from 1,340 to around 1,360 won. Supply disruptions at refining facilities in the Middle East and Russia have constrained refined-product supplies and supported margins. Yuanta Securities Korea projected SK Innovation’s annual operating profit could reach 10 trillion won if disruptions in oil refining and lubricants persist. iM Securities researcher Jeon Yu-jin said U.S. CDU operating rates had reached a historic 98% but remained insufficient to replace lost Middle Eastern and Russian supply, leaving margins unlikely to adjust easily ahead of winter. Aviation companies benefit from a stronger won because fuel and aircraft leases are largely dollar-denominated. Sangsangin Investment & Securities researcher Lee Seo-yeon said short-haul and long-haul travel demand, as well as high freight rates, remained favorable; a 13% decline in aviation fuel prices during July–August and a 50-won fall in the exchange rate could support airline profits if the lower exchange rate persists. Banks can gain foreign-exchange income when foreign assets are converted into won, potentially improving their Common Equity Tier 1 (CET1) ratio, a measure of core bank capital, and supporting dividends or buybacks. Hana Securities estimated Woori Financial Group could post about 130 billion won in third-quarter foreign-exchange gains. IBK Securities researcher Byun Jun-ho said expectations for further Federal Reserve rate increases within the year could strengthen the dollar and intensify foreign selling pressure on the KOSPI.