This excerpt taken from the NDAQ 8-K filed Dec 11, 2006.
The benefits of the combination of LSE and us may not be achieved if we cannot effect the compulsory acquisition of all of the issued and outstanding LSE shares.
To effect the compulsory acquisition of LSE shares for which valid acceptances have not been received under the offers under English law, we are required to have acquired at least 90% of the shares to which the offer relates. It is possible that, at the end of the offer period, we will not have acquired a sufficient number of LSE shares under the offers to effect a compulsory acquisition of the remaining outstanding LSE shares. This could prevent or delay us from realizing some or all of the anticipated benefits from the integration of our operations with LSEs operations.