diff --git a/proc.c b/proc.c
index 4f909dac4b..86610ddfd8 100644
--- a/proc.c
+++ b/proc.c
@@ -2725,6 +2725,7 @@ method_super_method(VALUE method)
 
     TypedData_Get_Struct(method, struct METHOD, &method_data_type, data);
     iclass = data->iclass;
+    if (!iclass) return Qnil;
     super_class = RCLASS_SUPER(RCLASS_ORIGIN(iclass));
     mid = data->me->called_id;
     if (!super_class) return Qnil;
diff --git a/test/ruby/test_method.rb b/test/ruby/test_method.rb
index e016662375..0ef913fd78 100644
--- a/test/ruby/test_method.rb
+++ b/test/ruby/test_method.rb
@@ -926,6 +926,11 @@ class TestMethod < Test::Unit::TestCase
     assert_equal(m1.source_location, m2.source_location, bug)
   end
 
+  def test_super_method_after_bind
+    assert_nil String.instance_method(:length).bind(String.new).super_method,
+      '[ruby-core:85231] [Bug #14421]'
+  end
+
   def rest_parameter(*rest)
     rest
   end