diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 46d16013ae..6926dd5ed9 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -459,6 +459,7 @@ def _CommonChecks(input_api, output_api):
                   r'^tools[\\\/]valgrind[\\\/].*\.py$',
                   r'^tools[\\\/]win[\\\/].*\.py$',
                   # TODO(phoglund): should arguably be checked.
+                  r'^tools-webrtc[\\\/]mb[\\\/].*\.py$',
                   r'^tools-webrtc[\\\/]valgrind[\\\/].*\.py$',
                   r'^xcodebuild.*[\\\/].*\.py$',),
       disabled_warnings=['F0401',  # Failed to import x
diff --git a/tools/mb/OWNERS b/tools-webrtc/mb/OWNERS
similarity index 100%
rename from tools/mb/OWNERS
rename to tools-webrtc/mb/OWNERS
diff --git a/tools/mb/PRESUBMIT.py b/tools-webrtc/mb/PRESUBMIT.py
similarity index 82%
rename from tools/mb/PRESUBMIT.py
rename to tools-webrtc/mb/PRESUBMIT.py
index a520ff9b29..d21aec1ded 100644
--- a/tools/mb/PRESUBMIT.py
+++ b/tools-webrtc/mb/PRESUBMIT.py
@@ -19,11 +19,7 @@ def _CommonChecks(input_api, output_api):
       input_api, output_api, '.', [ r'^.+_unittest\.py$']))
 
   # Validate the format of the mb_config.pyl file.
-  mb_config_path = input_api.os_path.join(input_api.PresubmitLocalPath(),
-                                          '..', '..', 'webrtc', 'build',
-                                          'mb_config.pyl')
-  cmd = [input_api.python_executable, 'mb.py', 'validate', '--config-file',
-         mb_config_path]
+  cmd = [input_api.python_executable, 'mb.py', 'validate']
   kwargs = {'cwd': input_api.PresubmitLocalPath()}
   results.extend(input_api.RunTests([
       input_api.Command(name='mb_validate',
diff --git a/tools/mb/README.md b/tools-webrtc/mb/README.md
similarity index 100%
rename from tools/mb/README.md
rename to tools-webrtc/mb/README.md
diff --git a/tools/mb/docs/README.md b/tools-webrtc/mb/docs/README.md
similarity index 100%
rename from tools/mb/docs/README.md
rename to tools-webrtc/mb/docs/README.md
diff --git a/tools/mb/docs/design_spec.md b/tools-webrtc/mb/docs/design_spec.md
similarity index 100%
rename from tools/mb/docs/design_spec.md
rename to tools-webrtc/mb/docs/design_spec.md
diff --git a/tools/mb/docs/user_guide.md b/tools-webrtc/mb/docs/user_guide.md
similarity index 100%
rename from tools/mb/docs/user_guide.md
rename to tools-webrtc/mb/docs/user_guide.md
diff --git a/tools/mb/mb b/tools-webrtc/mb/mb
similarity index 100%
rename from tools/mb/mb
rename to tools-webrtc/mb/mb
diff --git a/tools/mb/mb.bat b/tools-webrtc/mb/mb.bat
similarity index 100%
rename from tools/mb/mb.bat
rename to tools-webrtc/mb/mb.bat
diff --git a/tools/mb/mb.py b/tools-webrtc/mb/mb.py
similarity index 97%
rename from tools/mb/mb.py
rename to tools-webrtc/mb/mb.py
index 0b4f85e98b..77a81e0b5b 100755
--- a/tools/mb/mb.py
+++ b/tools-webrtc/mb/mb.py
@@ -32,8 +32,8 @@ import urllib2
 
 from collections import OrderedDict
 
-CHROMIUM_SRC_DIR = os.path.dirname(os.path.dirname(os.path.dirname(
-    os.path.abspath(__file__))))
+SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
+CHROMIUM_SRC_DIR = os.path.dirname(os.path.dirname(SCRIPT_DIR))
 sys.path = [os.path.join(CHROMIUM_SRC_DIR, 'build')] + sys.path
 
 import gn_helpers
@@ -47,8 +47,7 @@ def main(args):
 class MetaBuildWrapper(object):
   def __init__(self):
     self.chromium_src_dir = CHROMIUM_SRC_DIR
-    self.default_config = os.path.join(self.chromium_src_dir, 'tools', 'mb',
-                                       'mb_config.pyl')
+    self.default_config = os.path.join(SCRIPT_DIR, 'mb_config.pyl')
     self.default_isolate_map = os.path.join(self.chromium_src_dir, 'testing',
                                             'buildbot', 'gn_isolate_map.pyl')
     self.executable = sys.executable
@@ -421,29 +420,6 @@ class MetaBuildWrapper(object):
       if not mixin in referenced_mixins:
         errs.append('Unreferenced mixin "%s".' % mixin)
 
-    # If we're checking the Chromium config, check that the 'chromium' bots
-    # which build public artifacts do not include the chrome_with_codecs mixin.
-    if self.args.config_file == self.default_config:
-      if 'chromium' in self.masters:
-        for builder in self.masters['chromium']:
-          config = self.masters['chromium'][builder]
-          def RecurseMixins(current_mixin):
-            if current_mixin == 'chrome_with_codecs':
-              errs.append('Public artifact builder "%s" can not contain the '
-                          '"chrome_with_codecs" mixin.' % builder)
-              return
-            if not 'mixins' in self.mixins[current_mixin]:
-              return
-            for mixin in self.mixins[current_mixin]['mixins']:
-              RecurseMixins(mixin)
-
-          for mixin in self.configs[config]:
-            RecurseMixins(mixin)
-      else:
-        errs.append('Missing "chromium" master. Please update this '
-                    'proprietary codecs check with the name of the master '
-                    'responsible for public build artifacts.')
-
     if errs:
       raise MBErr(('mb config file %s has problems:' % self.args.config_file) +
                     '\n  ' + '\n  '.join(errs))
diff --git a/webrtc/build/mb_config.pyl b/tools-webrtc/mb/mb_config.pyl
similarity index 100%
rename from webrtc/build/mb_config.pyl
rename to tools-webrtc/mb/mb_config.pyl
diff --git a/tools/mb/mb_unittest.py b/tools-webrtc/mb/mb_unittest.py
similarity index 94%
rename from tools/mb/mb_unittest.py
rename to tools-webrtc/mb/mb_unittest.py
index fc69828d5a..3f9a6c9adb 100755
--- a/tools/mb/mb_unittest.py
+++ b/tools-webrtc/mb/mb_unittest.py
@@ -26,7 +26,7 @@ class FakeMBW(mb.MetaBuildWrapper):
     # Override vars for test portability.
     if win32:
       self.chromium_src_dir = 'c:\\fake_src'
-      self.default_config = 'c:\\fake_src\\tools\\mb\\mb_config.pyl'
+      self.default_config = 'c:\\fake_src\\tools-webrtc\\mb\\mb_config.pyl'
       self.default_isolate_map = ('c:\\fake_src\\testing\\buildbot\\'
                                   'gn_isolate_map.pyl')
       self.platform = 'win32'
@@ -34,7 +34,7 @@ class FakeMBW(mb.MetaBuildWrapper):
       self.sep = '\\'
     else:
       self.chromium_src_dir = '/fake_src'
-      self.default_config = '/fake_src/tools/mb/mb_config.pyl'
+      self.default_config = '/fake_src/tools-webrtc/mb/mb_config.pyl'
       self.default_isolate_map = '/fake_src/testing/buildbot/gn_isolate_map.pyl'
       self.executable = '/usr/bin/python'
       self.platform = 'linux2'
@@ -176,35 +176,6 @@ TEST_CONFIG = """\
 }
 """
 
-
-TEST_BAD_CONFIG = """\
-{
-  'configs': {
-    'gn_rel_bot_1': ['gn', 'rel', 'chrome_with_codecs'],
-    'gn_rel_bot_2': ['gn', 'rel', 'bad_nested_config'],
-  },
-  'masters': {
-    'chromium': {
-      'a': 'gn_rel_bot_1',
-      'b': 'gn_rel_bot_2',
-    },
-  },
-  'mixins': {
-    'gn': {'type': 'gn'},
-    'chrome_with_codecs': {
-      'gn_args': 'proprietary_codecs=true',
-    },
-    'bad_nested_config': {
-      'mixins': ['chrome_with_codecs'],
-    },
-    'rel': {
-      'gn_args': 'is_debug=false',
-    },
-  },
-}
-"""
-
-
 GYP_HACKS_CONFIG = """\
 {
   'masters': {
@@ -798,34 +769,6 @@ class UnitTest(unittest.TestCase):
     mbw = self.fake_mbw()
     self.check(['validate'], mbw=mbw, ret=0)
 
-  def test_bad_validate(self):
-    mbw = self.fake_mbw()
-    mbw.files[mbw.default_config] = TEST_BAD_CONFIG
-    self.check(['validate'], mbw=mbw, ret=1)
-
-  def test_gyp_env_hacks(self):
-    mbw = self.fake_mbw()
-    mbw.files[mbw.default_config] = GYP_HACKS_CONFIG
-    self.check(['lookup', '-c', 'fake_config'], mbw=mbw,
-               ret=0,
-               out=("GYP_DEFINES='foo=bar baz=1'\n"
-                    "GYP_LINK_CONCURRENCY=1\n"
-                    "LLVM_FORCE_HEAD_REVISION=1\n"
-                    "python build/gyp_chromium -G output_dir=_path_\n"))
-
-
-if __name__ == '__main__':
-  unittest.main()
-
-  def test_validate(self):
-    mbw = self.fake_mbw()
-    self.check(['validate'], mbw=mbw, ret=0)
-
-  def test_bad_validate(self):
-    mbw = self.fake_mbw()
-    mbw.files[mbw.default_config] = TEST_BAD_CONFIG
-    self.check(['validate'], mbw=mbw, ret=1)
-
   def test_gyp_env_hacks(self):
     mbw = self.fake_mbw()
     mbw.files[mbw.default_config] = GYP_HACKS_CONFIG
diff --git a/webrtc/build/PRESUBMIT.py b/webrtc/build/PRESUBMIT.py
deleted file mode 100644
index d364f862f2..0000000000
--- a/webrtc/build/PRESUBMIT.py
+++ /dev/null
@@ -1,34 +0,0 @@
-# Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
-#
-# Use of this source code is governed by a BSD-style license
-# that can be found in the LICENSE file in the root of the source
-# tree. An additional intellectual property rights grant can be found
-# in the file PATENTS.  All contributing project authors may
-# be found in the AUTHORS file in the root of the source tree.
-
-
-def _CommonChecks(input_api, output_api):
-  results = []
-
-  # Validate the format of the mb_config.pyl file.
-  mb_script = input_api.os_path.join(input_api.PresubmitLocalPath(), '..',
-                                     '..', 'tools', 'mb', 'mb.py')
-  mb_config_path = input_api.os_path.join(input_api.PresubmitLocalPath(),
-                                          'mb_config.pyl')
-  cmd = [input_api.python_executable, mb_script, 'validate', '--config-file',
-         mb_config_path]
-  kwargs = {'cwd': input_api.PresubmitLocalPath()}
-  results.extend(input_api.RunTests([
-      input_api.Command(name='mb_validate',
-                        cmd=cmd, kwargs=kwargs,
-                        message=output_api.PresubmitError)]))
-
-  return results
-
-
-def CheckChangeOnUpload(input_api, output_api):
-  return _CommonChecks(input_api, output_api)
-
-
-def CheckChangeOnCommit(input_api, output_api):
-  return _CommonChecks(input_api, output_api)