This excerpt taken from the NDAQ DEF 14A filed Apr 20, 2007.
Purchase of LSE Shares from Wellington Management Company
On May 3, 2006, our wholly-owned subsidiary Nightingale Acquisition Limited, a private limited company formed under the laws of England and Wales, purchased 9,790,280 shares, or 3.8% of the issued share capital, of the London Stock Exchange plc (LSE) at a price of GBP 12.18 per share, from Wellington Management Company, LLP or its affiliates. The total consideration represented approximately GBP 119.2 million, or $220.7 million, based on an exchange rate of 1.85 U.S. dollars per British pound as of May 4, 2006. We paid for the shares with cash on hand.
As of the record date, Wellington Management Company, LLP beneficially owned 15,335,375 million shares, or approximately 13.5% of our issued common stock. The share purchase was made in an ordinary market transaction with the terms determined through arms-length negotiation between the parties.