South Korean stocks closed lower on Monday as overseas investors offloaded securities ahead of the release of earnings for the April-June quarter.

Shares of major chipmaker SK Hynix (KRX:000660) declined 3.4% ahead of its planned $28 billion Nasdaq listing on July 10, while foreign selling and a weaker won weighed on the broader market. Samsung Electronics (KRX:005930), however, gained ahead of its second-quarter earnings release on Tuesday.

The benchmark Korea Composite Stock Price Index, or Kospi, fell by 0.5%, or 37.01 points, to close at 8,051.33. The Kosdaq, also decreased by 2.5%, or 21.34 points, to end at 847.07.

In corporate news, Hanwha Corp. (KRX:000880) on Friday said it plans to invest 55 trillion won in integrated space infrastructure and artificial intelligence sectors by 2040.

The company will build infrastructure that will comprise launch vehicles, ultra-low-orbit synthetic aperture radar (SAR) satellites, space-based AI data centers, and a low-Earth orbit (LEO) satellite communications network.

Hanwha Aerospace (KRX:012450) will invest about 23 trillion won in launch vehicles, while Hanwha Systems (KRX:272210) will spend 20 trillion won on satellites and communications infrastructure.

Shares of Hanwha Corp. rose more than 5% in Monday market close, while those of Hanwha Aerospace fell over 1%. Shares of Hanwha Systems added over 7%.

In other news, Hyundai Motor Group, the parent of Hyundai Motor (KRX:005380) and Kia (KRX:000270), plans to invest 42 trillion won in South Korea's Yeongnam region over 10 years beginning in 2026, according to a Friday release.

The group will invest in AI-defined vehicle manufacturing, core components, AI-driven manufacturing, aerospace and space, and sustainable energy infrastructure. The investments aim to boost future growth, create employment, and support balanced development across Yeongnam.

Shares of Hyundai Motor added over 2% at market close, while those of Kia jumped nearly 6%.