Seoul shares ended down on Friday to post their first weekly loss in five weeks after US House Speaker John Boehner abandoned his "fiscal cliff" plan, muddying the outlook for a deal to avert harsh spending cuts and tax hikes. Heavyweight Samsung Electronics slumped 4.1 percent, marking its biggest daily percentage decline since it lost a US patent lawsuit with Apple in August.
The Korea Composite Stock Price Index (KOSPI) finished down 0.95 percent at 1,980.42 points, marking a weekly loss of 0.7 percent. "Investors are disappointed by the latest development on fiscal talks. The market will continue to be swayed by the state of US budget negotiations," said Kim Soo-young, an analyst at KB Securities.
The KOSPI's Volatility Index jumped 9.4 percent, its biggest percentage gain in five months. Shares in Samsung Electronic, which account for nearly 20 percent of the KOSPI's market value, ended down at 1,442,000 Korean won ($1,300), after hitting a series of record-highs last week. "Samsung shares are undergoing a correction because they have risen so sharply in a short term," said Im Do-ri, a technical analyst at Shinyoung Securities.
EU regulators are poised to accuse Samsung Electronics of breaking competition rules in filing patent lawsuits against rival Apple, while Apple argued that a US appeals court should reconsider its decision to overturn a potential sales ban on Samsung for patent infringement. Banks and food/beverage firms, which are focused on domestic markets, bucked the market falls. Lender Korea Exchange Bank gained 1.5 percent, while noodle maker Nongshim ended up 3.1 percent. STX Corp went up 2.4 percent after Italian shipbuilder Fincantieri SpA announced a plan to acquire Singapore-listed STX OSV Holdings from a unit of STX Corp for $1.2 billion.