The New York Stock Exchange (NYSE) said that a technical issue that halted trading for some major stocks and caused Berkshire Hathaway to be down 99.97 per cent has been resolved.
In an update today, NYSE said impacted stocks have reopened and "all systems are currently operational."
Intercontinental Exchange (ICE), the parent company of NYSE, has found no indication the glitch was caused by a cyberattack, a senior executive at a major bank in touch with ICE told CNN.
Instead, an NYSE spokesperson said there was a "technical issue" with industry-wide price bands that "triggered" trading halts on up to 40 symbols listed on NYSE Group exchanges.
NYSE noted that those price bands are published by the Consolidated Tape Association's (CTA) Security Information Processor (SIP).
CTA, an industry group, is responsible for publishing real-time trade and quote data.
Dozens of stocks were paused earlier in the day, an indication they traded outside those so-called limit up-limit down bands, according to NYSE's website.
That list includes Chipotle and Berkshire Hathaway, the holding company run by legendary investor Warren Buffett, one of the wealthiest people in the world.
For nearly two hours, Berkshire Hathaway's Class A shares were listed as trading at just $US185.10 ($276.64), a price that would represent a loss of 99.97 per cent.
Berkshire closed at $US627,400 on Friday.
NYSE announced it has decided to "bust," or cancel, all "erroneous" trades for Berkshire between 9.50am and 9.51am (US Eastern Time) at or below $US603,718.30.
The exchange said that ruling is not eligible for appeal and indicated it could cancel other trades.
"We are monitoring the issue and engaging with market participants," a spokesperson for the Securities and Exchange Commission told CNN.
Joe Saluzzi, co-founder of Themis Trading, said that the NYSE's explanation is hard to square with the bizarre trades that hit the tape.
"I'm not buying that explanation. That doesn't make any sense to me," said Saluzzi, a market structure expert and author of Broken Markets.
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Trading data provided by Refinitiv shows that Berkshire Hathaway changed hands at $US620,700 as of 9.44.32 yesterday morning.
And then, without any explanation, the stock crashed to just $US185.10.
The technical issues did not appear to impact the broader stock market, which moved mostly lower on economic growth concerns.
Besides Berkshire, most of the halted stocks and exchanged traded funds (ETFs) were only trading slightly higher or lower.
