Seoul shares set their seventh consecutive record on Thursday as shipbuilders gained on new orders, while retailers rose after the central bank governor said domestic demand was looking better than expected.
But SK Corp shares ended lower, reversing earlier gains, after Standard & Poor's said a restructuring announced by the oil refiner would not lead the credit ratings agency to upgrade its ratings or outlook.
POSCO fell 0.52 percent to 386,000 won ahead of its earnings results. The world's no.3 steel maker posted after the market's close a bigger-than-expected jump in quarterly profit as strong global demand led to higher steel product prices.
The benchmark Korea Composite Stock Price Index (KOSPI) rose 0.81 percent to end at an all-time high of 1,525.61 points, its seventh record in as many trading sessions.
The main index has now risen 5 percent in April alone, more than its 3.99 percent gain for the whole of 2006. But the index's relative strength index has risen to 87.4, above the 70-point level at which investors tend to see a stock or share as overbought.
Heavy buying by foreign investors has helped the gains, although they ended net sellers on Thursday for the first time in eight sessions. Samsung Heavy Industries Co, the world's third-biggest shipbuilder, rose 1.89 percent to 26,950 won after announcing it had secured a 546.3 billion won ($586.5 million) order from an African shipper.
Shinsegae Co, the country's biggest discount store retailer, rose 2.14 percent to 572,000 won. Flat-panel makers extended gains as brokerages continue to upgrade their views on the sector after LG.Philips LCD Co Ltd posted on Tuesday a smaller-than-expected loss and a positive outlook for the year. LG.Philips rose 1.71 percent to 35,650 won.
But SK Corp fell 1.61 percent to 91,500 won, far off the record 96,600 it had hit early in the session. Hyundai Motor Co, the country's biggest auto maker, lost 0.90 percent to 65,700 won.