Nasdaq said Thursday it has halted all trading -- apparently the latest snafu to strike major exchanges and trading firms.
The halt affected scores of big-name stocks, including Apple Inc. and Google Inc., leaving small investors and others scrambling to find out what's happening in their stocks.
The cause of the glitch is unknown, although Nasdaq put an alert on its website related to something known as its securities information processor, which disseminates stock quotes.
The Nasdaq options markets released an update recommending that all firms route their orders elsewhere.
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All stocks listed on the New York Stock Exchange are trading normally, but trading in all Nasdaq-listed stocks and underlying options has been halted for about a half hour, Richard Adamonis, spokesman for NYSE Euronext, said around 10:15 a.m. Pacific time.