diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index db6a00ec9aa..7b293adadc2 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -2363,7 +2363,7 @@ module ts {
         function parseType(): TypeNode {
             // The rules about 'yield' only apply to actual code/expression contexts.  They don't
             // apply to 'type' contexts.  So we disable these parameters here before moving on.            
-            return doOutsideOfContext(ParserContextFlags.AllParameterFlags, parseTypeWorker);
+            return doOutsideOfContext(ParserContextFlags.TypeExcludesFlags, parseTypeWorker);
         }
 
         function parseTypeWorker(): TypeNode {
@@ -4363,15 +4363,9 @@ module ts {
             node.heritageClauses = parseHeritageClauses(/*isClassHeritageClause:*/ true);
 
             if (parseExpected(SyntaxKind.OpenBraceToken)) {
-                // ClassTail[Yield,GeneratorParameter,Await,AsyncParameter] : (Modified) See 14.5
-                //      [~GeneratorParameter,~AsyncParameter]ClassHeritage[?Yield,?Await]opt { ClassBody[?Yield,?Await]opt }
-                //      [+GeneratorParameter] ClassHeritageopt { ClassBodyopt }
-                //      [+AsyncParameter] ClassHeritageopt { ClassBodyopt }
-                
-                node.members = inGeneratorParameterOrAsyncParameterContext()
-                    ? doOutsideOfYieldAndAwaitContext(parseClassMembers)
-                    : parseClassMembers();
-
+                // ClassTail[Yield,Await] : (Modified) See 14.5
+                //      ClassHeritage[?Yield,?Await]opt { ClassBody[?Yield,?Await]opt }                
+                node.members = parseClassMembers();
                 parseExpected(SyntaxKind.CloseBraceToken);
             }
             else {
@@ -4384,24 +4378,16 @@ module ts {
         }
 
         function parseHeritageClauses(isClassHeritageClause: boolean): NodeArray<HeritageClause> {
-            // ClassTail[Yield,GeneratorParameter,Await,AsyncParameter] : (Modified) See 14.5
-            //      [~GeneratorParameter,~AsyncParameter]ClassHeritage[?Yield,?Await]opt { ClassBody[?Yield,?Await]opt }
-            //      [+GeneratorParameter] ClassHeritageopt { ClassBodyopt }
-            //      [+AsyncParameter] ClassHeritageopt { ClassBodyopt }
+            // ClassTail[Yield,Await] : (Modified) See 14.5
+            //      ClassHeritage[?Yield,?Await]opt { ClassBody[?Yield,?Await]opt }
 
             if (isHeritageClause()) {
-                return isClassHeritageClause && inGeneratorParameterOrAsyncParameterContext()
-                    ? doOutsideOfYieldAndAwaitContext(parseHeritageClausesWorker)
-                    : parseHeritageClausesWorker();
+                return parseList(ParsingContext.HeritageClauses, /*checkForStrictMode:*/ false, parseHeritageClause);
             }
 
             return undefined;
         }
 
-        function parseHeritageClausesWorker() {
-            return parseList(ParsingContext.HeritageClauses, /*checkForStrictMode:*/ false, parseHeritageClause);
-        }
-
         function parseHeritageClause() {
             if (token === SyntaxKind.ExtendsKeyword || token === SyntaxKind.ImplementsKeyword) {
                 let node = <HeritageClause>createNode(SyntaxKind.HeritageClause);
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 86b4113eecc..4de0f7fd98c 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -361,7 +361,9 @@ module ts {
         // Context flags passed as part of the modified ES6 grammar.
         YieldAndGeneratorParameterFlags = Yield | GeneratorParameter,
         AwaitAndAsyncParameterFlags = Await | AsyncParameter,
-        AllParameterFlags = YieldAndGeneratorParameterFlags | AwaitAndAsyncParameterFlags,       
+        
+        // Exclude these flags when parsing a Type
+        TypeExcludesFlags = YieldAndGeneratorParameterFlags | AwaitAndAsyncParameterFlags,       
         
         // Context flags computed by aggregating child flags upwards.