Comment Displacer Beast is *debatably* WotC property (Score 1) 35
,..because its original name is the Coeurl, from the novella The Black Destroyer by A E van Vogt (it showed up later in The Voyage of the Space Beagle, which was ripped off for Alien). There's no specific public record I can find of van Vogt or his estate providing an exclusive license (or ANY license) to TSR or WotC for them to claim ownership of something derived from the Coeurl.