The tech-heavy Nasdaq stock market said on Thursday it was halting trading in all securities until further notice due to a problem affecting quote dissemination.
Dozens of publicly traded companies, including high-profile companies such as Apple, Microsoft and Facebook, were showing their shares halted. The Nasdaq status message was time stamped at 12:14:03 ET.
A spokesman for the SEC said, "We are monitoring the situation and in are close contact with the exchanges."
The Nasdaq options markets also issued a "system update" saying they were recommending firms route all open orders elsewhere.
The New York Stock Exchange said it had halted trading in all Nasdaq securities at its request and was cancelling orders. The NYSE otherwise declined comment.
"You can't trade if you can't get the quotes out," said Rich Repetto of Sandler O'Neill Partners.