Seoul shares ended slightly lower Tuesday, the final trading session of 2025, as investors locked in profits despite gains in semiconductor stocks.

The benchmark Korea Composite Stock Price Index lost six‑point‑39 points, or zero‑point‑15 percent, to close the year at four‑thousand‑214‑point‑17.

Trading volume reached 398‑point‑49 million shares worth 12‑point‑69 trillion won, about eight‑point‑81 billion U.S. dollars, with decliners outnumbering gainers 544 to 329.

Large‑cap stocks ended mixed.

Samsung Electronics rose zero‑point‑33 percent to 119‑thousand‑900 won, hitting a record high amid a semiconductor upcycle. 

SK hynix climbed one‑point‑72 percent to 651‑thousand won, also reaching an all‑time high.

Automakers advanced, with Hyundai Motor up one‑point‑02 percent and Kia gaining zero‑point‑58 percent.

LG Energy Solution slipped three‑point‑03 percent, and Doosan Enerbility lost one‑point‑57 percent.

Shipbuilders also retreated. 

HD Hyundai Heavy dropped two‑point‑68 percent, while Hanwha Ocean lost one‑point‑73 percent.

Hanwha Aerospace declined zero‑point‑84 percent, and steelmaker POSCO shed two‑point‑87 percent.

The tech‑heavy KOSDAQ fell seven‑point‑12 points, or zero‑point‑76 percent, to close at 925‑point‑47.

The South Korean won weakened against the U.S. dollar by nine‑point‑two won, trading at one‑thousand‑439 won as of 3:30 p.m.

Trading will resume at 10 a.m. Friday.