diff --git a/lib/6to5/transformers/destructuring.js b/lib/6to5/transformers/destructuring.js
index 62f4ed757f..a214b6c5ba 100644
--- a/lib/6to5/transformers/destructuring.js
+++ b/lib/6to5/transformers/destructuring.js
@@ -27,7 +27,7 @@ var push = function (kind, nodes, elem, parentId) {
 var pushObjectPattern = function (kind, nodes, pattern, parentId) {
   _.each(pattern.properties, function (prop) {
     var pattern2   = prop.value;
-    var patternId2 = b.memberExpression(parentId, prop.key, false);
+    var patternId2 = b.memberExpression(parentId, prop.key);
 
     if (t.isPattern(pattern2)) {
       push(kind, nodes, pattern2, patternId2);
diff --git a/lib/6to5/transformers/for-of.js b/lib/6to5/transformers/for-of.js
index f535347eff..d051d07dd5 100644
--- a/lib/6to5/transformers/for-of.js
+++ b/lib/6to5/transformers/for-of.js
@@ -7,7 +7,7 @@ exports.ForOfStatement = function (node, parent, file) {
   var declar;
 
   var stepKey = b.identifier(file.generateUid("step"));
-  var stepValueId = b.memberExpression(stepKey, b.identifier("value"), false);
+  var stepValueId = b.memberExpression(stepKey, b.identifier("value"));
 
   if (left.type === "Identifier") {
     declar = b.expressionStatement(b.assignmentExpression("=", left, stepValueId));
diff --git a/lib/6to5/transformers/jsx.js b/lib/6to5/transformers/jsx.js
index 0065d9a029..72ae8a506f 100644
--- a/lib/6to5/transformers/jsx.js
+++ b/lib/6to5/transformers/jsx.js
@@ -18,7 +18,7 @@ exports.Program = function (node, parent, file) {
 
   // prebuilding AST node
   file.jsx = jsx.split(".").map(b.identifier).reduce(function (object, property) {
-    return b.memberExpression(object, property, false);
+    return b.memberExpression(object, property);
   });
 };
 
@@ -67,7 +67,7 @@ exports.XJSOpeningElement = {
       var tagName = tagExpr.name;
 
       if (/[a-z]/.exec(tagName[0]) || _.contains(tagName, "-")) {
-        tagExpr = b.memberExpression(file.jsx, tagExpr, false);
+        tagExpr = b.memberExpression(file.jsx, tagExpr);
       }
     }
 
diff --git a/lib/6to5/transformers/spread.js b/lib/6to5/transformers/spread.js
index 862d21e60b..dcb9cee196 100644
--- a/lib/6to5/transformers/spread.js
+++ b/lib/6to5/transformers/spread.js
@@ -58,7 +58,7 @@ exports.ArrayExpression = function (node, parent, file) {
 
   if (!nodes.length) return first;
 
-  return b.callExpression(b.memberExpression(first, b.identifier("concat"), false), nodes);
+  return b.callExpression(b.memberExpression(first, b.identifier("concat")), nodes);
 };
 
 exports.CallExpression = function (node, parent, file) {
@@ -73,7 +73,7 @@ exports.CallExpression = function (node, parent, file) {
   var first = nodes.shift();
 
   if (nodes.length) {
-    node.arguments.push(b.callExpression(b.memberExpression(first, b.identifier("concat"), false), nodes));
+    node.arguments.push(b.callExpression(b.memberExpression(first, b.identifier("concat")), nodes));
   } else {
     node.arguments.push(first);
   }
@@ -88,10 +88,10 @@ exports.CallExpression = function (node, parent, file) {
       callee.property = b.identifier("apply");
       callee.computed = false;
     } else {
-      callee.property = b.memberExpression(callee.property, b.identifier("apply"), false);
+      callee.property = b.memberExpression(callee.property, b.identifier("apply"));
     }
   } else {
-    node.callee = b.memberExpression(node.callee, b.identifier("apply"), false);
+    node.callee = b.memberExpression(node.callee, b.identifier("apply"));
   }
 
   node.arguments.unshift(contextLiteral);