(AP) -- The CEO of the Nasdaq stock exchange says it is "humbly embarrassed" by its bungling of Facebook's hugely anticipated debut as a public company on Friday.
Robert Greifeld tells news media there's no indication the delay contributed to the underwhelming performance of Facebook's stock, which ended at $38.23 - 23 cents above where it began.
Facebook's stock was expected to start trading at 11 a.m. but didn't open until 11:32 a.m., and some investors didn't learn for hours whether their orders went through.
Greifeld called the social network's first day of trading "successful." He said late order cancellations caused a glitch, according to reports published Sunday. He said Nasdaq's board met Saturday and plans to change its IPO auction process.
The Securities and Exchange Commission has said it is investigating.
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