This excerpt taken from the NDAQ 10-Q filed Nov 9, 2007.
Secondary Offering of NASDAQ Common Stock
On November 8, 2007, we announced that H&F sold 23,545,368 shares of our common stock in a public offering. The shares sold consisted of shares issued through the conversion of the 3.75% convertible notes issued to H&F, the cashless exercise of the warrants issued to H&F, as well as shares held outright by H&F. As part of the cashless exercise of warrants, H&F delivered to us 1,044,276 shares of our common stock, which we will hold as treasury shares. The sale consisted of H&Fs entire stake in Nasdaq. Nasdaq will not receive any of the proceeds from the offering.