diff --git a/src/calibre/db/search.py b/src/calibre/db/search.py
index 9eeacc24b5..6a6fbb0a56 100644
--- a/src/calibre/db/search.py
+++ b/src/calibre/db/search.py
@@ -290,8 +290,11 @@ class NumericSearch(object):  # {{{
                 raise ParseException(
                         _('Non-numeric value in query: {0}').format(query))
 
+        qfalse = query == 'false'
         for val, book_ids in field_iter():
             if val is None:
+                if qfalse:
+                    matches |= book_ids
                 continue
             try:
                 v = cast(val)
diff --git a/src/calibre/db/tests/reading.py b/src/calibre/db/tests/reading.py
index 56866f5aa7..c9d29475f6 100644
--- a/src/calibre/db/tests/reading.py
+++ b/src/calibre/db/tests/reading.py
@@ -224,8 +224,8 @@ class ReadingTest(BaseTest):
             'rating:3', 'rating:>2', 'rating:=2', 'rating:true',
             'rating:false', 'rating:>4', 'tags:#<2', 'tags:#>7',
             'cover:false', 'cover:true', '#float:>11', '#float:<1k',
-            '#float:10.01', 'series_index:1', 'series_index:<3', 'id:1',
-            'id:>2',
+            '#float:10.01', '#float:false', 'series_index:1',
+            'series_index:<3', 'id:1', 'id:>2',
 
             # Bool tests
             '#yesno:true', '#yesno:false', '#yesno:yes', '#yesno:no',