On the 12th, the KOSPI once again hit a record high. Since the new year, it has set a new closing record high for seven straight sessions. The KOSPI swept past a fresh intraday high from early trading, and as buying spread from semiconductors to the broad "jobangwon" (shipbuilding, defense, nuclear power) group, it finished at a record high on a closing basis.
The KOSPI finished the session at 4,624.79, up 38.47 points (0.84%) from the previous session. It opened at 4,639.89, up 53.57 points (1.17%) from the prior close, and briefly crossed the 4,650 level on strong individual buying early on. It briefly turned lower just before the close, but then recovered a slight gain.
Kim Seok-hwan, a researcher at Mirae Asset Securities, said, "As foreigners have been net sellers for three straight sessions and the won-dollar exchange rate has risen for eight straight sessions to near 1,470 won, that led the KOSPI to turn lower," adding, "With key events ahead this week, including Greenland, the U.S. Supreme Court ruling, and the Venezuela and Iran situations, profit-taking and risk-off sentiment are strengthening."
In the main board, individuals and institutions were net buyers by about 13 billion won and 290 billion won, respectively. Foreign investors were net sellers by about 540 billion won.
Among top market-cap stocks on the main board, moves were mixed. With bellwether semiconductor stocks Samsung Electronics (-0.14%) and SK hynix (0.67%) showing no clear direction, shares of LG Energy Solution (4.41%) and Korea Electric Power Corporation (3.24%) rose. In contrast, Samsung Biologics (-1.01%) and Kia (-2.93%) ended at lower prices than the previous session.
Buying flocked to some jobangwon leaders. Shipbuilders gained as detailed policies related to MASGA became visible and expectations for South Korea-U.S. shipbuilding cooperation stood out, lifting Hanwha Ocean (8.41%), Daehan Shipbuilding (5.65%), and HD Hyundai Heavy Industries (0.78%). In addition, as news emerged that U.S. President Donald Trump could consider military intervention in the Iran protests, some defense names, including Korea Aerospace Industries (2.74%) and MNC Solution (9.81%), also closed higher.
Lee Kyung-min, a researcher at Daishin Securities Co., said, "Semiconductor and defense stocks, which rose sharply last week, paused for breath, but flows shifted to defense and shipbuilding, which can benefit together, and a rotational rally is underway."
Nuclear power stocks also extended a rally. Investor sentiment was stoked by news that Meta, operator of Facebook, signed large-scale nuclear power contracts with nuclear corporations to secure electricity for its artificial intelligence (AI) data centers. Doosan Enerbility (4.63%), Hyundai E&C (20.18%), BHI (3.7%), and KEPCO E&C (5.24%) rose.
Hyundai Motor Group affiliates also caught a tailwind. At "CES 2026," the world's largest consumer electronics and information technology (IT) trade show that wrapped up last week, Hyundai Motor Group's humanoid robot "Atlas" won positive reviews. Shares of key affiliates, including Hyundai Motor (0.27%) and Hyundai GLOVIS (7.51%), rose.
The KOSDAQ closed at 949.81, up 1.89 points (0.2%) from the previous session. The index opened at 948.48, up 0.56 points (0.06%) from the prior close, and, after briefly turning lower on foreign selling, it slightly recovered gains on individual buying.
On the KOSDAQ, individuals alone were net buyers by about 97 billion won. Foreigners and institutions were net sellers by about 7 billion won and 66 billion won, respectively.
Among the top 10 KOSDAQ stocks by market cap, six fell. Alteogen (-6.95%), ABL Bio (-1.47%), and LigaChem Biosciences (-2.59%) declined. In contrast, secondary-battery bellwethers ECOPRO BM (6.62%) and EcoPro (6.59%), as well as HLB (7.71%) and Samchundang Pharm (5.68%), ended at higher prices than the previous session.
In the Seoul foreign exchange market, the won-dollar exchange rate stood at 1,468.40 won as of 3:30 p.m., up 10.8 won from the previous close.