Originally Posted by http://www.vbulletin.com/license-agreement/1.1

Limited Use. You may not transfer, rent, sublicense, assign, lease, loan, resell for profit, redistribute, encumber, publish or otherwise share the Software (or related materials based upon the Software or any part thereof) without the prior written consent of vBulletin Solutions. You must not use the Software other than as permitted by the License or in a manner inconsistent with its design and Documentation. If you are domiciled in the E.U., please refer to Section 19.