diff --git a/src/wanijo/schema/domain.clj b/src/wanijo/schema/domain.clj
index d60da92..4e0ba75 100644
--- a/src/wanijo/schema/domain.clj
+++ b/src/wanijo/schema/domain.clj
@@ -10,8 +10,7 @@
 
 (spec/def ::assigned-to
   (spec/or :public empty?
-           :assigned (spec/coll-of string?)
-           :single string?))
+           :assigned (spec/coll-of string?)))
 
 (neo4j/defquery
   all-created-by