diff --git a/src/Compilers/CSharp/Portable/Parser/Lexer.cs b/src/Compilers/CSharp/Portable/Parser/Lexer.cs
index 895a2bf752ea2e445d762dd34dea64bdc0e0d7b9..f52fd1efe8acb65167b203d6bd1c403d71745005 100644
--- a/src/Compilers/CSharp/Portable/Parser/Lexer.cs
+++ b/src/Compilers/CSharp/Portable/Parser/Lexer.cs
@@ -674,12 +674,6 @@ private void ScanSyntaxToken(ref TokenInfo info)
                     break;
 
                 case '<':
-                    if (this.ModeIs(LexerMode.DebuggerSyntax) && TextWindow.PeekChar(1) == '>')
-                    {
-                        // For "<>f_AnonymousType", which is an identifier in DebuggerSyntax mode
-                        goto case 'a';
-                    }
-
                     TextWindow.AdvanceChar();
                     if (TextWindow.PeekChar() == '=')
                     {
@@ -688,13 +682,6 @@ private void ScanSyntaxToken(ref TokenInfo info)
                     }
                     else if (TextWindow.PeekChar() == '<')
                     {
-                        if (this.ModeIs(LexerMode.DebuggerSyntax) && TextWindow.PeekChar(1) == '>')
-                        {
-                            // For "GenericOf<<>f__AnonymousType>"
-                            info.Kind = SyntaxKind.LessThanToken;
-                            break;
-                        }
-
                         TextWindow.AdvanceChar();
                         if (TextWindow.PeekChar() == '=')
                         {
diff --git a/src/Compilers/CSharp/Test/Syntax/LexicalAndXml/LexicalTests.cs b/src/Compilers/CSharp/Test/Syntax/LexicalAndXml/LexicalTests.cs
index 3c92b4d6f94fa8c93214da27fa155d3c9d12ea17..101c6bf8ca516a415436a12da227cdbf527495ee 100644
--- a/src/Compilers/CSharp/Test/Syntax/LexicalAndXml/LexicalTests.cs
+++ b/src/Compilers/CSharp/Test/Syntax/LexicalAndXml/LexicalTests.cs
@@ -2282,79 +2282,6 @@ public void TestDottedNameSequence()
             Assert.Equal(6, results.Count);
         }
 
-        [Fact]
-        public void TestDebuggerCompilerGeneratedIdentifiers()
-        {
-            string text = "<>";
-            var token = DebuggerLexToken(text);
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.IdentifierToken, token.Kind());
-            var errors = token.Errors();
-            Assert.Equal(0, errors.Length);
-            Assert.Equal(text, token.Text);
-            Assert.Equal(text, token.Value);
-
-            text = "<>f__AnonymousType0";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.IdentifierToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal(text, token.Text);
-            Assert.Equal(text, token.Value);
-
-            text = "<>f__AnonymousType0>";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.IdentifierToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal(text.Substring(0, text.Length - 1), token.Text);
-            Assert.Equal(text.Substring(0, text.Length - 1), token.Value);
-
-            text = "<>f__AnonymousType0<";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.IdentifierToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal(text.Substring(0, text.Length - 1), token.Text);
-            Assert.Equal(text.Substring(0, text.Length - 1), token.Value);
-
-            text = "<>f__\\u0041nonymousType1";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.IdentifierToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal(text, token.Text);
-            Assert.NotEqual(text, token.Value);
-            Assert.Equal("<>f__AnonymousType1", token.Value);
-
-            text = "<<>";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.LessThanToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal("<", token.Text);
-
-            text = "<<X";
-            token = DebuggerLexToken(text);
-            errors = token.Errors();
-
-            Assert.NotNull(token);
-            Assert.Equal(SyntaxKind.LessThanLessThanToken, token.Kind());
-            Assert.Equal(0, errors.Length);
-            Assert.Equal("<<", token.Text);
-        }
-
         [Fact]
         public void TestDebuggerDollarIdentifiers()
         {
diff --git a/src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/ExpressionCompilerTests.cs b/src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/ExpressionCompilerTests.cs
index 47728098652577a1cbca954778de982981fcf9f5..f2df1ee2029323685fb9bee2ba4cb2a7b018cb6b 100644
--- a/src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/ExpressionCompilerTests.cs
+++ b/src/ExpressionEvaluator/CSharp/Test/ExpressionCompiler/ExpressionCompilerTests.cs
@@ -5915,5 +5915,52 @@ .maxstack  1
 }
 ");
         }
+
+        [WorkItem(1136085, "DevDiv")]
+        [Fact]
+        public void TypeofOpenGenericType()
+        {
+            var source = @"
+using System;
+
+public class C
+{
+    public void M()
+    {
+    }
+}";
+            var compilation = CreateCompilationWithMscorlib45(source);
+            var runtime = CreateRuntimeInstance(compilation);
+            var context = CreateMethodContext(runtime, "C.M");
+
+            string error;
+            var expectedIL = @"
+{
+  // Code size       11 (0xb)
+  .maxstack  1
+  IL_0000:  ldtoken    ""System.Action<T>""
+  IL_0005:  call       ""System.Type System.Type.GetTypeFromHandle(System.RuntimeTypeHandle)""
+  IL_000a:  ret
+}";
+
+            var testData = new CompilationTestData();
+            context.CompileExpression("typeof(Action<>)", out error, testData);
+            Assert.Null(error);
+            testData.GetMethodData("<>x.<>m0").VerifyIL(expectedIL);
+
+            testData = new CompilationTestData();
+            context.CompileExpression("typeof(Action<>  )", out error, testData);
+            Assert.Null(error);
+            testData.GetMethodData("<>x.<>m0").VerifyIL(expectedIL);
+
+            context.CompileExpression("typeof(Action<Action<>>)", out error, testData);
+            Assert.Equal("error CS7003: Unexpected use of an unbound generic name", error);
+
+            context.CompileExpression("typeof(Action<Action< > > )", out error);
+            Assert.Equal("error CS7003: Unexpected use of an unbound generic name", error);
+
+            context.CompileExpression("typeof(Action<>a)", out error);
+            Assert.Equal("(1,16): error CS1026: ) expected", error);
+        }
     }
 }
diff --git a/src/ExpressionEvaluator/VisualBasic/Test/ExpressionCompiler/ExpressionCompilerTests.vb b/src/ExpressionEvaluator/VisualBasic/Test/ExpressionCompiler/ExpressionCompilerTests.vb
index b1290dabf85ae5c9552cfd8f11b7bf95d0f14045..80cf0a8e8b6442817b89a54c3e83ea1ea97407d7 100644
--- a/src/ExpressionEvaluator/VisualBasic/Test/ExpressionCompiler/ExpressionCompilerTests.vb
+++ b/src/ExpressionEvaluator/VisualBasic/Test/ExpressionCompiler/ExpressionCompilerTests.vb
@@ -3942,6 +3942,33 @@ End Module"
 }")
         End Sub
 
+        <Fact>
+        Public Sub GetTypeOpenGenericType()
+            Dim source = "
+Imports System
+
+Class C
+    Sub M()
+    End Sub
+End Class"
+            Dim compilation = CreateCompilationWithMscorlib({source}, compOptions:=TestOptions.DebugDll)
+            Dim runtime = CreateRuntimeInstance(compilation)
+            Dim context = CreateMethodContext(runtime, "C.M")
+
+            Dim errorMessage As String = Nothing
+            Dim testData = New CompilationTestData()
+            context.CompileExpression("GetType(Action(Of ))", errorMessage, testData)
+            Assert.Null(errorMessage)
+            testData.GetMethodData("<>x.<>m0").VerifyIL("
+{
+  // Code size       11 (0xb)
+  .maxstack  1
+  IL_0000:  ldtoken    ""System.Action(Of T)""
+  IL_0005:  call       ""Function System.Type.GetTypeFromHandle(System.RuntimeTypeHandle) As System.Type""
+  IL_000a:  ret
+}")
+        End Sub
+
     End Class
 
 End Namespace
\ No newline at end of file