diff --git a/spot/twaalgos/toparity.cc b/spot/twaalgos/toparity.cc
index 37cf999f9..3688a6983 100644
--- a/spot/twaalgos/toparity.cc
+++ b/spot/twaalgos/toparity.cc
@@ -833,19 +833,21 @@ const std::vector<unsigned>& states,
 std::map<unsigned, std::vector<unsigned>>& partial_history,
 state_2_car_scc& state_2_car)
 {
-    for (unsigned current_state : states)
-        for (auto& edge : aut->out(current_state))
-        {
-            unsigned
-                src = edge.src,
-                dst = edge.dst;
-            if (src == dst)
-                continue;
-            unsigned dst_scc = num2car[dst].state_scc;
-            auto cant_change = partial_history[aut->edge_number(edge)];
-            edge.dst = state_2_car.get_sub_tree(cant_change, dst_scc)
-                                 ->get_end(true);
-        }
+    for (auto& edge : aut->edges())
+    {
+        unsigned
+            src = edge.src,
+            dst = edge.dst;
+        // We don't change loops or transitions that were not created in
+        // the current SCC.
+        if (src == dst
+        || std::find(states.begin(), states.end(), src) == states.end())
+            continue;
+        unsigned dst_scc = num2car[dst].state_scc;
+        auto cant_change = partial_history[aut->edge_number(edge)];
+        edge.dst = state_2_car.get_sub_tree(cant_change, dst_scc)
+                                ->get_end(true);
+    }
 }
 
 unsigned
diff --git a/spot/twaalgos/toparity.hh b/spot/twaalgos/toparity.hh
index 055711551..fb4984342 100644
--- a/spot/twaalgos/toparity.hh
+++ b/spot/twaalgos/toparity.hh
@@ -63,9 +63,9 @@ namespace spot
     /// Only allow degeneralization if it reduces the number of colors in the
     /// acceptance condition.
     bool reduce_col_deg = false;
-    /// Use propagate_marks_here to increase the number of marks on transition in
-    /// order to move more colors (and increase the number of compatible states)
-    /// when we apply LAR.
+    /// Use propagate_marks_here to increase the number of marks on transition
+    /// in order to move more colors (and increase the number of
+    /// compatible states) when we apply LAR.
     bool propagate_col  = true;
     /// If \a pretty_print is true, states of the output automaton are
     /// named to help debugging.
diff --git a/tests/python/merge.py b/tests/python/merge.py
index 161b9b6fd..a33a2774f 100644
--- a/tests/python/merge.py
+++ b/tests/python/merge.py
@@ -78,7 +78,8 @@ assert hoa == """HOA: v1
 States: 3
 Start: 0
 AP: 2 "a" "b"
-Acceptance: 2 Fin(1) | Inf(0)
+acc-name: parity min even 2
+Acceptance: 2 Inf(0) | Fin(1)
 properties: trans-labels explicit-labels trans-acc
 --BODY--
 State: 0
diff --git a/tests/python/toparity.py b/tests/python/toparity.py
index 95c01ad61..d06a72206 100644
--- a/tests/python/toparity.py
+++ b/tests/python/toparity.py
@@ -288,7 +288,7 @@ State: 4
 [0&!1] 4
 [0&1] 4 {1 2 4}
 --END--
-"""), [9, 6, 6, 6, 7, 6, 6])
+"""), [9, 6, 7, 7, 6, 6, 6])
 
 test(spot.automaton("""
 HOA: v1