Updated: Nasdaq-Listed Equities, ETFs, and Options Resume Trading After 'Flash Freeze'

Nasdaq, meanwhile, says it will not be canceling open orders as a result of the glitch, a decision which it has left to individual customers' discretion, and processed 'stale' orders once normal trading resumed in full at 3.25 pm. Until then, Nasdaq had advised clients to route elsewhere as it investigated the malfunction. Without price updates, however, only a handful of dark pool venues continued with trades on the affected listings, while trading volume in equities listed elsewhere but indirectly related, e.g. by industry, to those affected also fell off during what is being called a 'flash freeze'.

In an unrelated issue, CME Group is examining its soy futures complex at the Chicago Board of Trade (CBOT), after data in that market appeared to list some products at prices higher than anticipated by conventional market behavior. A CME spokesperson says trading was not disrupted.

The latest glitches comes after revelations this week that Goldman Sachs placed errorneous orders on a handful of options because of a software problem, which is now being investigated by the US Securities and Exchange Commission (SEC) and could end up costing the investment bank millions as the cancelled trades are unwound. In a statement, the SEC says it is monitoring today's situation closely as well.

Further updates to come as new details emerge.