(9)In order to limit the administrative burdens for parties using financial collateral under the scope of this Directive, the only perfection requirement which national law may impose in respect of financial collateral should be that the financial collateral is delivered, transferred, held, registered or otherwise designated so as to be in the possession or under the control of the collateral taker or of a person acting on the collateral taker's behalf while not excluding collateral techniques where the collateral provider is allowed to substitute collateral or to withdraw excess collateral.