The Collaborative International Dictionary of English v.0.48:
Unowned \Un*own"ed\, a. [Pref. un- not + (sense 1) owned possessed, and (sense 2) owned granted, acknowledged.] [1913 Webster] 1. Not owned; having no owner. --Milton. [1913 Webster] 2. Not acknowledged; not avowed. --Gay. [1913 Webster]WordNet (r) 3.0 (2006):
unowned adj 1: having no owner [syn: unowned, ownerless] [ant: owned]