Maldonado v. Matthews
In Maldonado v. Matthews, 2010 WL 663723 (Del. Super. 2010) the Superior Court held that certified mailings returned as unclaimed may be sufficient proof of notice.
In Maldonado, the Plaintiff "took additional steps beyond just sending one mailing," sent multiple mailings both to the address of record, and to another potential address through which Defendants might receive notice, and filed proof of non-receipt with the Court.
The Court in Maldonado found that "these additional steps demonstrate that Plaintiff took all steps that 'reasonably could be done.'" Id.