diff --git a/nipype/interfaces/ants/registration.py b/nipype/interfaces/ants/registration.py
index de95d09e1b..03cbbd76eb 100644
--- a/nipype/interfaces/ants/registration.py
+++ b/nipype/interfaces/ants/registration.py
@@ -235,7 +235,7 @@ class RegistrationInputSpec(ANTSCommandInputSpec):
     initial_moving_transform = File(argstr='%s', exists=True, desc='',
                                     xor=['initial_moving_transform_com'])
     invert_initial_moving_transform = traits.Bool(
-        default=False, requires=["initial_moving_transform"],
+        default=False, requires=["initial_moving_transform"], usedefault=True,
         desc='', xor=['initial_moving_transform_com'])
 
     initial_moving_transform_com = traits.Enum(0, 1, 2, argstr='%s',