Asian shares have declined, with South Korea's Kospi index experiencing a significant drop. The index plunged over 10% due to heavy selling of chipmaking stocks. This decline is attributed to concerns about the sustainability of the artificial intelligence boom.

Oil prices have also fallen, decreasing by more than 1%. US futures, however, remained relatively unchanged. The Kospi index reached its lowest level since April, with shares of major chipmakers like Samsung Electronics and SK Hynix dropping sharply.

Further details on this development are available from KSAT 12. The decline in Asian shares and the Kospi index may have implications for global markets, but specific effects on San Antonio are not specified in the available information.