A human error at a New York Stock Exchange data center in Chicago, wherein backup systems were left running, caused the exchange’s computers to treat Tuesday’s opening bell as a continuation of the previous day’s trades.
The opening auction that normally sets prices did not occur.
“On January 24, 2023, at approximately 9:30 AM, the NYSE commenced continuous trading in 2,824 of 3,421 NYSE-listed securities without attempting to conduct an opening auction due to a technical issue,” the NYSE indicated on its website.
The commencement of continued trading in lieu of the expected opening auction that sets prices caused 84 listed stocks to be paused after hitting price band benchmarks that prevent security prices from spiking or plummeting too far too fast.