UPDATE 3:25 p.m. ET –  All Nasdaq trading has resumed. Markets seem to have taken the 3-hour halt in stride:

Nasdaq Makes Rare Call to Halt All TradingIt is still unclear what prompted the outage.

UPDATE 2:48 p.m. ET– Bloomberg News reports that all trading will resume at 3:25 p.m. ET. However, this marks the sixth time that the Nasdaq’s relaunch time has been moved forward.

We’ll see if it’s for real this time.

UPDATE 1:51 p.m. ET — Unconfirmed reports claim the Nasdaq should be back online within one hourand CNBC is on it:

Nasdaq Makes Rare Call to Halt All Trading

@dashbot

UPDATE 1:38 p.m. ET –  Here’s something worth noting:

$5.7 trillion locked up by Nasdaq trading halt $NDAQ $COMP http://t.co/twrzHWcEJJ
Nasdaq Makes Rare Call to Halt All Trading
@lauramandaro
Laura Mandaro

UPDATE 1:26 p.m. ET –The Wall Street Journal reports Nasdaq trading is expected to resume shortly.

An alleged technical issue forced exchange officials on Thursday to halt all trading in securities listed on the Nasdaq Stock Market:

Nasdaq Makes Rare Call to Halt All Trading

It’s flatlining !

The Wall Street Journal offers some detail:

Nasdaq OMX Group Inc. announced the halt at 12:15 p.m. ET Thursday, and other exchanges followed suit. Nasdaq also said it was halting trade in its options markets. A spokesman for Nasdaq declined further comment.

Notices of halts in individual securities started to cross the wire at about 12:18 p.m. ET in alphabetical order by ticker symbol, starting with the exchange-traded fund iShares MSCI All Country Asia Information Technology ETF, AAIT -0.18%

As of this writing, it is uncertain what prompted the trading halt. Certain news outlets have cited unknown technical errors, but these have yet to be confirmed.

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