Del. Code Ann. tit. 6, § 8-503
(d) An entitlement holder’s property interest with respect to a particular financial asset under subsection (a) may be enforced against a purchaser of the financial asset or interest therein only if:
The trustee or other liquidator, acting on behalf of all entitlement holders having security entitlements with respect to a particular financial asset, may recover the financial asset, or interest therein, from the purchaser. If the trustee or other liquidator elects not to pursue that right, an entitlement holder whose security entitlement remains unsatisfied has the right to recover its interest in the financial asset from the purchaser.