An odd thing happened before the stock market close yesterday. Google's stock was mostly flat all day, until 3:57 p.m., when it dropped severely. The shares, which opened Tuesday at $419.51, rose to a high of $423.51, then mysteriously plunged roughly 10 percent to $341.43 just minutes before the closing bell.
It turns out that the stock's drop was the result of erroneous trades sent from another exchange, according to a Nasdaq spokeswoman (via Dealbook).
According to Nasdaq OMX, which operates the Nasdaq stock market ... In a message posted on its Web site, Nasdaq said it was adjusting Google's closing share price to $400.52, or up 5.12 percent, and that it was canceling trades above $425.29 or below $400.52 made at or after 3:57 p.m.
Nasdaq said late Tuesday that it is "investigating potentially erroneous transactions," but didn't offer more details.