South Korean stocks opened a tad lower Thursday, tracking overnight losses on Wall Street led by declines in big-cap tech shares. The benchmark Korea Composite Stock Price Index (Kospi) shed 3.05 points, or 0.12 percent, to 2,500.01 in the first 15 minutes of trading. Foreigners were on a selling mode, which offset buying by institutions and retail investors. Overnight, the Dow Jones Industrial Average fell 0.31 percent and the tech-heavy Nasdaq composite slid 0.6 percent as major tech shares lo