Yahoo Finance Samsung Shares Plunge Over Galaxy S4 Fears
South Korea's benchmark index has fallen the most in nearly 11 months, hit by Samsung which tumbled 6.2% on jitters about its slowing smartphone growth.
Samsung's drop, the biggest in nine months, wiped more than £7.7bn from the company's market capitalisation, according to Reuters.
Fears have been raised that the electronics giant will not be able to maintain momentum with its top mobile devices, after it introduced two slimmed down models.
It also follows a report that arch-rival Apple (NasdaqGS: AAPL - news) will begin a trade-in programme for iPhones.
Shares of Samsung account for about one-fifth of the KOSPI exchange's value.
Sparked by brokerages' downgrades, it marked the biggest daily percentage loss since August last year when the smartphone giant lost a US patent lawsuit to Apple.
The latest drop came after a 16.6% fall in forecasts of global sales for Samsung's premier phone.
"After market talk of Galaxy S4 sell-ins being worse-than-expected, third-quarter sales forecasts are seen revised down from 30 million to 25 million handsets sold," said Song Jong-ho, head of tech sector research at KDB Daewoo Securities.
Concerns about reduced margins in the mobile phone market, due to increased competition, was also seen dragging on sentiment for the tech giant.
Other local blue chips compounded Friday's decline as foreign investors sold off during the day.
Foreign investors have started getting jitters about ongoing US fiscal stimulus, and the weakening dollar.
"Concerns about a possible reduction in the Federal Reserve's stimulus measures remain," Hanyang Securities analyst Lim Dong-rak said.
"As well as readjustments in market expectations for Japan's reflationary policies, there appears to be dampening short-term foreign inflows."
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