diff --git a/bottleneck/src/move_template.c b/bottleneck/src/move_template.c
index 8a589703d..4d5682e01 100644
--- a/bottleneck/src/move_template.c
+++ b/bottleneck/src/move_template.c
@@ -989,6 +989,8 @@ mover(char *name,
 
     length = PyArray_DIM(a, axis);
     if ((window < 1) || (window > length)) {
+        return a;
+        
         PyErr_Format(PyExc_ValueError,
                      "Moving window (=%d) must between 1 and %zu, inclusive",
                      window, length);