Trading on the biggest exchange for financial options finally materialized Thursday after a long outage apparently caused by software problems had delayed the opening.
The Chicago Board Options Exchange reopened just before 1 p.m. after being closed from the start of the trading day. The shutdown forced traders to scramble for alternatives.
The outage came in the wake of a brief scare in financial markets Tuesday afternoon when hackers sent a false Associated Press tweet reporting explosions at the White House. Stocks prices plunged for two minutes as computerized trading systems unloaded equities. Regulators are increasingly looking into the safety of computerized trading systems.