An undertaking by a debtor to a lender not to create, or permit to subsist, security or otherwise encumber certain of its assets in certain circumstances without the prior written consent of the lender. It is a covenant usually found in a loan agreement or in the terms of a bond. In a bond, it may simply prohibit the creation of security in certain circumstances unless the same security is created for the bond on a pari passu basis. The purpose of a negative pledge is to ensure that other creditors do not obtain a preferred claim over the assets of the debtor in the event of insolvency.