diff --git a/src/calibre/gui2/custom_column_widgets.py b/src/calibre/gui2/custom_column_widgets.py
index fed1de93a1..96232fe85f 100644
--- a/src/calibre/gui2/custom_column_widgets.py
+++ b/src/calibre/gui2/custom_column_widgets.py
@@ -167,7 +167,7 @@ class DateTime(Base):
 
     def getter(self):
         val = self.widgets[1].date()
-        if val <= UNDEFINED_QDATE:
+        if val == UNDEFINED_QDATE:
             val = None
         else:
             val = qt_to_dt(val)