diff --git a/NEWS b/NEWS
index 0c8c59540..c1073d13c 100644
--- a/NEWS
+++ b/NEWS
@@ -112,6 +112,8 @@ New in spot 2.5.3.dev  (not yet released)
   - The HOA parser will now accept Alias: declarations that occur
     before AP:.
 
+  - the option --allow-dups of randltl now works properly
+
 New in spot 2.5.3 (2018-04-20)
 
   Bugs fixed:
diff --git a/bin/randltl.cc b/bin/randltl.cc
index dd6bce180..47bfdb3bf 100644
--- a/bin/randltl.cc
+++ b/bin/randltl.cc
@@ -267,6 +267,7 @@ main(int argc, char** argv)
           opts.set("wf", opt_wf);
           opts.set("seed", opt_seed);
           opts.set("simplification_level", simplification_level);
+          opts.set("unique", opt_unique);
           return opts;
         }(), opt_pL, opt_pS, opt_pB);
 
diff --git a/tests/core/rand.test b/tests/core/rand.test
index c5cdf9b67..267c411a8 100755
--- a/tests/core/rand.test
+++ b/tests/core/rand.test
@@ -1,6 +1,6 @@
 #!/bin/sh
 # -*- coding: utf-8 -*-
-# Copyright (C) 2014, 2015, 2017 Laboratoire de Recherche et
+# Copyright (C) 2014, 2015, 2017, 2018 Laboratoire de Recherche et
 # Développement de l'Epita (LRDE).
 #
 # This file is part of Spot, a model checking library.
@@ -138,3 +138,10 @@ diff test-cmp.ltl test-all.ltl
 
 randltl 2 --ltl-prio=X 2>stderr && exit 1
 grep 'failed to parse LTL priorities near X' stderr
+
+randltl -L --allow-dups -n2 1 > out
+cat >expected <<EOF
+0
+0
+EOF
+diff out expected