Nasdaq OMX chief Robert Greifeld has said he is "humbly embarrassed" by the technical glitch that held up Facebook's IPO on Friday.
Greifeld said that problems with order cancellations interfered with the social network's debut, delaying it by more than two hours from the ringing of the bell at 9am EDT.
"This was not our finest hour," he told reporters in a conference call on Sunday, according to the Wall Street Journal.
He also said that Nasdaq would be making changes to its auction process, but he didn't reveal any details.
Nasdaq had performed extensive testing beforehand and hadn't spotted the problem, but a malfunction apparently sent the stock exchanges systems into a loop that stopped the shares from coming online on schedule.
Some are blaming the technical problems for the poor performance of Facebook shares on Friday; the stock closed at just 0.6 per cent above the IPO price despite the preceding public anticipation of a big bump.
Traders said that investors got cold feet after having to wait over two hours after the stock started trading to see if their initial orders had been honoured or cancelled in the technical hiccup. Since they didn't know for sure how much they'd bought or sold and at what price, they bailed out.
The problems aren't the first technical issues to come up on newly computerised stock exchanges. In May 2010, a computer-driven sale worth $4.1bn triggered a "flash crash" that temporarily wiped out $1 trillion worth of shareholder equity in minutes.
In March this year, the US's third-largest stock exchange, BATS Global Markets, had to withdraw its own IPO on its own exchange after a series of unforeseen glitches. ®