diff --git a/collects/redex/redex.scrbl b/collects/redex/redex.scrbl
index a0db170618..b452bf1d84 100644
--- a/collects/redex/redex.scrbl
+++ b/collects/redex/redex.scrbl
@@ -821,10 +821,9 @@ arguments would have stepped.
 }
 
 @defproc[(reduction-relation->rule-names [r reduction-relation?])
-         (listof (union false/c symbol?))]{
+         (listof symbol?)]{
 
-Returns the names of all of the reduction relation's clauses
-(or false if there is no name for a given clause).
+Returns the names of the reduction relation's named clauses.
 }
 
 @defform[(compatible-closure reduction-relation lang non-terminal)]{