diff --git a/clang/lib/Sema/SemaObjCProperty.cpp b/clang/lib/Sema/SemaObjCProperty.cpp
--- a/clang/lib/Sema/SemaObjCProperty.cpp
+++ b/clang/lib/Sema/SemaObjCProperty.cpp
@@ -225,43 +225,56 @@
   if (Res->getType().getObjCLifetime())
     checkPropertyDeclWithOwnership(*this, Res);
 
-  llvm::SmallPtrSet<ObjCProtocolDecl *, 16> KnownProtos;
-  if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
-    // For a class, compare the property against a property in our superclass.
-    bool FoundInSuper = false;
-    ObjCInterfaceDecl *CurrentInterfaceDecl = IFace;
-    while (ObjCInterfaceDecl *Super = CurrentInterfaceDecl->getSuperClass()) {
-      if (ObjCPropertyDecl *SuperProp =
-          Super->lookup(Res->getDeclName()).find_first<ObjCPropertyDecl>()) {
-        DiagnosePropertyMismatch(Res, SuperProp, Super->getIdentifier(), false);
-        FoundInSuper = true;
-        break;
+  // For an instance property, check consistency with the properties of
+  // superclasses.
+  if (Res->isInstanceProperty()) {
+    llvm::SmallPtrSet<ObjCProtocolDecl *, 16> KnownProtos;
+    if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(ClassDecl)) {
+      // For a class, compare the property against a property in our superclass.
+      bool FoundInSuper = false;
+      ObjCInterfaceDecl *CurrentInterfaceDecl = IFace;
+      while (ObjCInterfaceDecl *Super = CurrentInterfaceDecl->getSuperClass()) {
+        ObjCPropertyDecl *SuperProp = nullptr;
+        for (auto *LookupResult : Super->lookup(Res->getDeclName())) {
+          if (auto *Prop = dyn_cast<ObjCPropertyDecl>(LookupResult)) {
+            if (Prop->isInstanceProperty()) {
+              SuperProp = Prop;
+              break;
+            }
+          }
+        }
+        if (SuperProp) {
+          DiagnosePropertyMismatch(Res, SuperProp, Super->getIdentifier(),
+                                   false);
+          FoundInSuper = true;
+          break;
+        }
+        CurrentInterfaceDecl = Super;
       }
-      CurrentInterfaceDecl = Super;
-    }
 
-    if (FoundInSuper) {
-      // Also compare the property against a property in our protocols.
-      for (auto *P : CurrentInterfaceDecl->protocols()) {
-        CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
+      if (FoundInSuper) {
+        // Also compare the property against a property in our protocols.
+        for (auto *P : CurrentInterfaceDecl->protocols()) {
+          CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
+        }
+      } else {
+        // Slower path: look in all protocols we referenced.
+        for (auto *P : IFace->all_referenced_protocols()) {
+          CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
+        }
       }
+    } else if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
+      // We don't check if class extension. Because properties in class
+      // extension are meant to override some of the attributes and checking has
+      // already done when property in class extension is constructed.
+      if (!Cat->IsClassExtension())
+        for (auto *P : Cat->protocols())
+          CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
     } else {
-      // Slower path: look in all protocols we referenced.
-      for (auto *P : IFace->all_referenced_protocols()) {
+      ObjCProtocolDecl *Proto = cast<ObjCProtocolDecl>(ClassDecl);
+      for (auto *P : Proto->protocols())
         CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
-      }
     }
-  } else if (ObjCCategoryDecl *Cat = dyn_cast<ObjCCategoryDecl>(ClassDecl)) {
-    // We don't check if class extension. Because properties in class extension
-    // are meant to override some of the attributes and checking has already done
-    // when property in class extension is constructed.
-    if (!Cat->IsClassExtension())
-      for (auto *P : Cat->protocols())
-        CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
-  } else {
-    ObjCProtocolDecl *Proto = cast<ObjCProtocolDecl>(ClassDecl);
-    for (auto *P : Proto->protocols())
-      CheckPropertyAgainstProtocol(*this, Res, P, KnownProtos);
   }
 
   ActOnDocumentableDecl(Res);
diff --git a/clang/test/SemaObjC/class-property-inheritance.m b/clang/test/SemaObjC/class-property-inheritance.m
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaObjC/class-property-inheritance.m
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+// expected-no-diagnostics
+
+@class MyObject;
+
+@interface TopClassWithInstanceProperty
+@property(nullable, readonly, strong) MyObject *foo;
+@end
+
+@interface SubClassWithClassProperty : TopClassWithInstanceProperty
+@property(nonnull, readonly, copy, class) MyObject *foo;
+@end
+
+@interface TopClassWithClassProperty
+@property(nullable, readonly, class) MyObject *foo;
+@end
+
+@interface SubClassWithInstanceProperty : TopClassWithClassProperty
+@property(nonnull, readonly, copy) MyObject *foo;
+@end