diff --git a/src/Umbraco.Core/Persistence/Factories/MemberTypeReadOnlyFactory.cs b/src/Umbraco.Core/Persistence/Factories/MemberTypeReadOnlyFactory.cs
index b4d5d2e566..ba7a47165b 100644
--- a/src/Umbraco.Core/Persistence/Factories/MemberTypeReadOnlyFactory.cs
+++ b/src/Umbraco.Core/Persistence/Factories/MemberTypeReadOnlyFactory.cs
@@ -9,9 +9,10 @@ namespace Umbraco.Core.Persistence.Factories
 {
     internal class MemberTypeReadOnlyFactory 
     {
-        public IMemberType BuildEntity(MemberTypeReadOnlyDto dto)
+        public IMemberType BuildEntity(MemberTypeReadOnlyDto dto, out bool needsSaving)
         {
             var standardPropertyTypes = Constants.Conventions.Member.GetStandardPropertyTypeStubs();
+            needsSaving = false;
 
             var memberType = new MemberType(dto.ParentId);
 
@@ -47,6 +48,12 @@ namespace Umbraco.Core.Persistence.Factories
                 {
                     if (dto.PropertyTypes.Any(x => x.Alias.Equals(standardPropertyType.Key))) continue;
 
+                    // beware!
+                    // means that we can return a memberType "from database" that has some property types
+                    // that do *not* come from the database and therefore are incomplete eg have no key,
+                    // no id, no dataTypeDefinitionId - ouch! - better notify caller of the situation
+                    needsSaving = true;
+
                     //Add the standard PropertyType to the current list
                     propertyTypes.Add(standardPropertyType.Value);
 
diff --git a/src/Umbraco.Core/Persistence/Repositories/MemberTypeRepository.cs b/src/Umbraco.Core/Persistence/Repositories/MemberTypeRepository.cs
index d06399a85b..7d5defe8c9 100644
--- a/src/Umbraco.Core/Persistence/Repositories/MemberTypeRepository.cs
+++ b/src/Umbraco.Core/Persistence/Repositories/MemberTypeRepository.cs
@@ -300,13 +300,19 @@ namespace Umbraco.Core.Persistence.Repositories
         /// </summary>
         /// <param name="dtos"></param>
         /// <returns></returns>
-        private static IEnumerable<IMemberType> BuildFromDtos(List<MemberTypeReadOnlyDto> dtos)
+        private IEnumerable<IMemberType> BuildFromDtos(List<MemberTypeReadOnlyDto> dtos)
         {
             if (dtos == null || dtos.Any() == false)
                 return Enumerable.Empty<IMemberType>();
 
             var factory = new MemberTypeReadOnlyFactory();
-            return dtos.Select(factory.BuildEntity);
+            return dtos.Select(x =>
+            {
+                bool needsSaving;
+                var memberType = factory.BuildEntity(x, out needsSaving);
+                if (needsSaving) PersistUpdatedItem(memberType);
+                return memberType;
+            }).ToList();
         }
 
         /// <summary>