diff --git a/presubmit_canned_checks.py b/presubmit_canned_checks.py
index 5b972d63e..9588fb0eb 100644
--- a/presubmit_canned_checks.py
+++ b/presubmit_canned_checks.py
@@ -213,8 +213,16 @@ def CheckChangeHasNoTabs(input_api, output_api, source_file_filter=None):
   """Checks that there are no tab characters in any of the text files to be
   submitted.
   """
+  # In addition to the filter, make sure that makefiles are blacklisted.
+  if not source_file_filter:
+    # It's the default filter.
+    source_file_filter = input_api.FilterSourceFile
+  def filter_more(affected_file):
+    return (not input_api.os_path.basename(affected_file.LocalPath()) in
+                ('Makefile', 'makefile') and
+            source_file_filter(affected_file))
   tabs = []
-  for f, line_num, line in input_api.RightHandSideLines(source_file_filter):
+  for f, line_num, line in input_api.RightHandSideLines(filter_more):
     if '\t' in line:
       tabs.append('%s, line %s' % (f.LocalPath(), line_num))
   if tabs:
diff --git a/tests/presubmit_unittest.py b/tests/presubmit_unittest.py
index 24a8844da..7928a2480 100755
--- a/tests/presubmit_unittest.py
+++ b/tests/presubmit_unittest.py
@@ -1161,6 +1161,7 @@ class CannedChecksUnittest(PresubmitTestsBase):
     input_api1 = self.MockInputApi(change1, False)
     affected_file = self.mox.CreateMock(presubmit.SvnAffectedFile)
     affected_file.LocalPath().AndReturn('foo.cc')
+    # Format is (file, line number, line content)
     output1 = [
       (affected_file, 42, 'yo, ' + content1),
       (affected_file, 43, 'yer'),
@@ -1327,6 +1328,44 @@ class CannedChecksUnittest(PresubmitTestsBase):
                      'blah blah', 'blah\tblah',
                      presubmit.OutputApi.PresubmitPromptWarning)
 
+    # Make sure makefiles are ignored.
+    change1 = presubmit.Change('foo1', 'foo1\n', self.fake_root_dir, None,
+                               0, 0)
+    input_api1 = self.MockInputApi(change1, False)
+    affected_file1 = self.mox.CreateMock(presubmit.SvnAffectedFile)
+    affected_file1.LocalPath().AndReturn('foo.cc')
+    affected_file2 = self.mox.CreateMock(presubmit.SvnAffectedFile)
+    affected_file2.LocalPath().AndReturn('foo/Makefile')
+    affected_file3 = self.mox.CreateMock(presubmit.SvnAffectedFile)
+    affected_file3.LocalPath().AndReturn('makefile')
+    # Only this one will trigger.
+    affected_file4 = self.mox.CreateMock(presubmit.SvnAffectedFile)
+    affected_file4.LocalPath().AndReturn('makefile.foo')
+    affected_file4.LocalPath().AndReturn('makefile.foo')
+    output1 = [
+      (affected_file1, 42, 'yo, '),
+      (affected_file2, 43, 'yer\t'),
+      (affected_file3, 45, 'yr\t'),
+      (affected_file4, 46, 'ye\t'),
+    ]
+    def test(source_filter):
+      for i in output1:
+        if source_filter(i[0]):
+          yield i
+    # Override the mock of these functions.
+    input_api1.FilterSourceFile = lambda x: x
+    input_api1.RightHandSideLines = test
+    self.mox.ReplayAll()
+
+    results1 = presubmit_canned_checks.CheckChangeHasNoTabs(input_api1,
+        presubmit.OutputApi, None)
+    self.assertEquals(len(results1), 1)
+    self.assertEquals(results1[0].__class__,
+        presubmit.OutputApi.PresubmitPromptWarning)
+    self.assertEquals(results1[0]._long_text,
+        'makefile.foo, line 46')
+
+
   def testCannedCheckLongLines(self):
     check = lambda x,y,z: presubmit_canned_checks.CheckLongLines(x, y, 10, z)
     self.ContentTest(check, '', 'blah blah blah',