(AP) — Trading has been halted in Nasdaq-listed securities because of a technical problem.
As a result of the Nasdaq snafu, the Chicago Board Options Exchange, the largest U.S. options exchange, halted trading in options linked to Nasdaq stocks at 11:23 a.m. CST. The exchange is owned and operated by CBOE Holdings Inc. A CBOE spokeswoman couldn’t immediately say what percentage of its options trading was affected.
Chicago-based CBOE also stopped trading on its small CBOE stock exchange at 11:21 a.m. and on its all-electronic C2 options exchange at 11:25 a.m.
The exchange sent out an alert to traders at 12:20 p.m. EDT saying that trading was being halted until further notice because of problems with a quote dissemination system.
Nasdaq said it wouldn’t be canceling any open orders.
The Wall Street Journal reports that the outage “saw a large chunk of the U.S. stock market effectively come to a standstill at midday, freezing prices in stocks, exchange-traded funds and options listed on Nasdaq and prompting other trading venues to stop trading those securities. Nasdaq-listed stocks represent about 28% of all shares traded so far this month, according to BATS Global Markets Inc.”
“The episode meant a widely tracked market gauge, the Nasdaq Composite Index, wasn’t being updated for the first time in memory. Trading was halted at 12:14 p.m. ET. The outage was also expected to skew the calculation of other major market measures such as the Dow Jones Industrial Average and the S&P 500-stock index . . . The issue stemmed from a data feed that provides market data for Nasdaq-listed securities, exchanges said in notices sent to traders,” the Journal writes.