diff --git a/clang/lib/Parse/ParseObjc.cpp b/clang/lib/Parse/ParseObjc.cpp
index 4a572f199328..607b953aad41 100644
--- a/clang/lib/Parse/ParseObjc.cpp
+++ b/clang/lib/Parse/ParseObjc.cpp
@@ -1541,6 +1541,12 @@ Parser::ParseObjCAtImplementationDeclaration(SourceLocation AtLoc) {
       return DeclGroupPtrTy();
     }
     rparenLoc = ConsumeParen();
+    if (Tok.is(tok::less)) { // we have illegal '<' try to recover
+      Diag(Tok, diag::err_unexpected_protocol_qualifier);
+      AttributeFactory attr;
+      DeclSpec DS(attr);
+      (void)ParseObjCProtocolQualifiers(DS);
+    }
     ObjCImpDecl = Actions.ActOnStartCategoryImplementation(
                                     AtLoc, nameId, nameLoc, categoryId,
                                     categoryLoc);
diff --git a/clang/test/Parser/objc-error-qualified-implementation.m b/clang/test/Parser/objc-error-qualified-implementation.m
index 444fb5dab44c..8bbd50236027 100644
--- a/clang/test/Parser/objc-error-qualified-implementation.m
+++ b/clang/test/Parser/objc-error-qualified-implementation.m
@@ -19,3 +19,11 @@
 
 @implementation K <P // expected-error {{@implementation declaration can not be protocol qualified}}
 @end // expected-error {{expected '>'}}
+
+// rdar://13920026
+@implementation I (Cat) <P>  // expected-error {{@implementation declaration can not be protocol qualified}}
+- (void) Meth {}
+@end
+
+@implementation I (Cat1) <P // expected-error {{@implementation declaration can not be protocol qualified}}
+@end // expected-error {{expected '>'}}