diff --git a/lib/6to5/util.js b/lib/6to5/util.js
index 244ab28cab..7bfe4e5ac3 100644
--- a/lib/6to5/util.js
+++ b/lib/6to5/util.js
@@ -117,6 +117,8 @@ exports.buildDefineProperties = function (mutatorMap) {
 
     var propNode = t.property("init", map._key, mapNode, map._computed);
 
+    map.enumerable = t.literal(true);
+
     _.each(map, function (node, key) {
       if (key[0] === "_") return;
 
diff --git a/test/fixtures/transformation/es5-property-methods-assignment/getter-and-setter/expected.js b/test/fixtures/transformation/es5-property-methods-assignment/getter-and-setter/expected.js
index 23467f3675..9ef3d3265d 100644
--- a/test/fixtures/transformation/es5-property-methods-assignment/getter-and-setter/expected.js
+++ b/test/fixtures/transformation/es5-property-methods-assignment/getter-and-setter/expected.js
@@ -8,7 +8,8 @@ var obj = (function (_obj) {
       },
       set: function (value) {
         this._foo = value;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es5-property-methods-assignment/getter/expected.js b/test/fixtures/transformation/es5-property-methods-assignment/getter/expected.js
index fda0188e6e..c519a4ee8d 100644
--- a/test/fixtures/transformation/es5-property-methods-assignment/getter/expected.js
+++ b/test/fixtures/transformation/es5-property-methods-assignment/getter/expected.js
@@ -5,7 +5,8 @@ var obj = (function (_obj) {
     foo: {
       get: function () {
         return 5 + 5;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es5-property-methods-assignment/setter/expected.js b/test/fixtures/transformation/es5-property-methods-assignment/setter/expected.js
index 3320d6ee41..780fb983a8 100644
--- a/test/fixtures/transformation/es5-property-methods-assignment/setter/expected.js
+++ b/test/fixtures/transformation/es5-property-methods-assignment/setter/expected.js
@@ -5,7 +5,8 @@ var obj = (function (_obj) {
     foo: {
       set: function (value) {
         this._foo = value;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es6-classes/instance-getter-and-setter/expected.js b/test/fixtures/transformation/es6-classes/instance-getter-and-setter/expected.js
index 0fb4c995d3..1ca4e4bc91 100644
--- a/test/fixtures/transformation/es6-classes/instance-getter-and-setter/expected.js
+++ b/test/fixtures/transformation/es6-classes/instance-getter-and-setter/expected.js
@@ -15,7 +15,8 @@ var Test = (function () {
       },
       set: function (val) {
         this._test = val;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es6-classes/instance-getter/expected.js b/test/fixtures/transformation/es6-classes/instance-getter/expected.js
index 0d50b8e732..b980afd00a 100644
--- a/test/fixtures/transformation/es6-classes/instance-getter/expected.js
+++ b/test/fixtures/transformation/es6-classes/instance-getter/expected.js
@@ -12,7 +12,8 @@ var Test = (function () {
     test: {
       get: function () {
         return 5 + 5;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es6-classes/instance-setter/expected.js b/test/fixtures/transformation/es6-classes/instance-setter/expected.js
index 87f8e40dde..5a181cc25c 100644
--- a/test/fixtures/transformation/es6-classes/instance-setter/expected.js
+++ b/test/fixtures/transformation/es6-classes/instance-setter/expected.js
@@ -12,7 +12,8 @@ var Test = (function () {
     test: {
       set: function (val) {
         this._test = val;
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/es6-classes/static/expected.js b/test/fixtures/transformation/es6-classes/static/expected.js
index 1ef2108334..26ef9d30f1 100644
--- a/test/fixtures/transformation/es6-classes/static/expected.js
+++ b/test/fixtures/transformation/es6-classes/static/expected.js
@@ -13,7 +13,8 @@ var A = (function () {
   _classProps(A, {
     b: {
       get: function () {},
-      set: function (b) {}
+      set: function (b) {},
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/playground/object-getter-memoization/expected.js b/test/fixtures/transformation/playground/object-getter-memoization/expected.js
index 83441a35f4..c8886b8b37 100644
--- a/test/fixtures/transformation/playground/object-getter-memoization/expected.js
+++ b/test/fixtures/transformation/playground/object-getter-memoization/expected.js
@@ -14,7 +14,8 @@ var Foo = (function () {
         if (this._memoDone) return this._memo;
         this._memoDone = true;
         return this._memo = complex();
-      }
+      },
+      enumerable: true
     };
     return _ref;
   })({
@@ -23,7 +24,8 @@ var Foo = (function () {
         if (this._barDone) return this._bar;
         this._barDone = true;
         return this._bar = complex();
-      }
+      },
+      enumerable: true
     }
   }));
 
@@ -45,7 +47,8 @@ var foo = (function (_foo) {
         if (this._barDone) return this._bar;
         this._barDone = true;
         return this._bar = complex();
-      }
+      },
+      enumerable: true
     }
   });
 
diff --git a/test/fixtures/transformation/source-maps/class/expected.js b/test/fixtures/transformation/source-maps/class/expected.js
index 7a04a39640..aa5136a46f 100644
--- a/test/fixtures/transformation/source-maps/class/expected.js
+++ b/test/fixtures/transformation/source-maps/class/expected.js
@@ -12,7 +12,8 @@ var Test = (function () {
     bar: {
       get: function () {
         throw new Error("wow");
-      }
+      },
+      enumerable: true
     }
   });