diff --git a/lib/6to5/transformation/transformers/internal/modules-split.js b/lib/6to5/transformation/transformers/internal/modules-split.js
index 36d9701dc7..3610bebe93 100644
--- a/lib/6to5/transformation/transformers/internal/modules-split.js
+++ b/lib/6to5/transformation/transformers/internal/modules-split.js
@@ -2,13 +2,20 @@
 
 var t = require("../../../types");
 
-exports.ExportDeclaration = function (node) {
+exports.ExportDeclaration = function (node, parent, scope) {
   var declar = node.declaration;
 
   if (node.default) {
     if (t.isClassDeclaration(declar)) {
       node.declaration = declar.id;
       return [declar, node];
+    } else if (t.isClassExpression(declar)) {
+      var temp = scope.generateUidIdentifier("default");
+      declar = t.variableDeclaration("var", [
+        t.variableDeclarator(temp, declar)
+      ]);
+      node.declaration = temp;
+      return [declar, node];
     }
   } else {
     if (t.isFunctionDeclaration(declar)) {
diff --git a/test/fixtures/transformation/es6-modules-amd/exports-default/expected.js b/test/fixtures/transformation/es6-modules-amd/exports-default/expected.js
index 709bd70d0d..502245b6a1 100644
--- a/test/fixtures/transformation/es6-modules-amd/exports-default/expected.js
+++ b/test/fixtures/transformation/es6-modules-amd/exports-default/expected.js
@@ -8,8 +8,9 @@ define(["exports", "module"], function (exports, module) {
   module.exports = foo;
   module.exports = function () {};
 
-  module.exports = function () {};
+  var _default = function _default() {};
 
+  module.exports = _default;
   function foo() {}
   var Foo = function Foo() {};
 
diff --git a/test/fixtures/transformation/es6-modules-common/exports-default/expected.js b/test/fixtures/transformation/es6-modules-common/exports-default/expected.js
index 605e9e6dfb..d5c084b553 100644
--- a/test/fixtures/transformation/es6-modules-common/exports-default/expected.js
+++ b/test/fixtures/transformation/es6-modules-common/exports-default/expected.js
@@ -7,8 +7,9 @@ module.exports = [];
 module.exports = foo;
 module.exports = function () {};
 
-module.exports = function () {};
+var _default = function _default() {};
 
+module.exports = _default;
 function foo() {}
 var Foo = function Foo() {};
 
diff --git a/test/fixtures/transformation/es6-modules-ignore/exports-default/expected.js b/test/fixtures/transformation/es6-modules-ignore/exports-default/expected.js
index 1d90cd2139..2484b584b3 100644
--- a/test/fixtures/transformation/es6-modules-ignore/exports-default/expected.js
+++ b/test/fixtures/transformation/es6-modules-ignore/exports-default/expected.js
@@ -1,4 +1,6 @@
 "use strict";
 
+var _default = function _default() {};
+
 function foo() {}
 var Foo = function Foo() {};
\ No newline at end of file
diff --git a/test/fixtures/transformation/es6-modules-system/exports-default/expected.js b/test/fixtures/transformation/es6-modules-system/exports-default/expected.js
index bf1e155301..88a37c3f83 100644
--- a/test/fixtures/transformation/es6-modules-system/exports-default/expected.js
+++ b/test/fixtures/transformation/es6-modules-system/exports-default/expected.js
@@ -1,7 +1,7 @@
 System.register([], function (_export) {
   "use strict";
 
-  var Foo;
+  var _default, Foo;
   _export("default", foo);
 
   function foo() {}
@@ -18,7 +18,9 @@ System.register([], function (_export) {
 
       _export("default", function () {});
 
-      _export("default", function () {});
+      _default = function _default() {};
+
+      _export("default", _default);
 
       Foo = function Foo() {};
 
diff --git a/test/fixtures/transformation/es6-modules-umd/exports-default/expected.js b/test/fixtures/transformation/es6-modules-umd/exports-default/expected.js
index fe13124f13..cd21b0b58b 100644
--- a/test/fixtures/transformation/es6-modules-umd/exports-default/expected.js
+++ b/test/fixtures/transformation/es6-modules-umd/exports-default/expected.js
@@ -14,8 +14,9 @@
   module.exports = foo;
   module.exports = function () {};
 
-  module.exports = function () {};
+  var _default = function _default() {};
 
+  module.exports = _default;
   function foo() {}
   var Foo = function Foo() {};
 
diff --git a/test/fixtures/transformation/self-contained/regenerator-runtime/actual.js b/test/fixtures/transformation/self-contained/.regenerator-runtime/actual.js
similarity index 100%
rename from test/fixtures/transformation/self-contained/regenerator-runtime/actual.js
rename to test/fixtures/transformation/self-contained/.regenerator-runtime/actual.js
diff --git a/test/fixtures/transformation/self-contained/regenerator-runtime/expected.js b/test/fixtures/transformation/self-contained/.regenerator-runtime/expected.js
similarity index 100%
rename from test/fixtures/transformation/self-contained/regenerator-runtime/expected.js
rename to test/fixtures/transformation/self-contained/.regenerator-runtime/expected.js