diff --git a/packages/ember-metal/lib/dependent_keys.js b/packages/ember-metal/lib/dependent_keys.js
index 27a2b075bab..29996d6a38f 100644
--- a/packages/ember-metal/lib/dependent_keys.js
+++ b/packages/ember-metal/lib/dependent_keys.js
@@ -1,7 +1,3 @@
-'no use strict';
-// Remove "use strict"; from transpiled module until
-// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
-
 import {
   watch,
   unwatch
diff --git a/packages/ember-metal/lib/events.js b/packages/ember-metal/lib/events.js
index 75c53884d00..4e139912e66 100644
--- a/packages/ember-metal/lib/events.js
+++ b/packages/ember-metal/lib/events.js
@@ -1,7 +1,3 @@
-'no use strict';
-// Remove "use strict"; from transpiled module until
-// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
-
 /**
 @module ember
 @submodule ember-metal
diff --git a/packages/ember-metal/lib/meta.js b/packages/ember-metal/lib/meta.js
index 7ab8fe66847..769f31cb477 100644
--- a/packages/ember-metal/lib/meta.js
+++ b/packages/ember-metal/lib/meta.js
@@ -1,7 +1,3 @@
-'no use strict';
-// Remove "use strict"; from transpiled module until
-// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
-
 import {
   HAS_NATIVE_WEAKMAP,
   EmptyObject,
diff --git a/packages/ember-metal/lib/mixin.js b/packages/ember-metal/lib/mixin.js
index 76d1e508ec9..f8e9ca86506 100644
--- a/packages/ember-metal/lib/mixin.js
+++ b/packages/ember-metal/lib/mixin.js
@@ -1,7 +1,3 @@
-'no use strict';
-// Remove "use strict"; from transpiled module until
-// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
-
 /**
 @module ember
 @submodule ember-metal
diff --git a/packages/ember-runtime/lib/system/core_object.js b/packages/ember-runtime/lib/system/core_object.js
index 08a9bcee949..32653281522 100644
--- a/packages/ember-runtime/lib/system/core_object.js
+++ b/packages/ember-runtime/lib/system/core_object.js
@@ -1,7 +1,3 @@
-'no use strict';
-// Remove "use strict"; from transpiled module until
-// https://bugs.webkit.org/show_bug.cgi?id=138038 is fixed
-
 /**
   @module ember
   @submodule ember-runtime