diff --git a/.gitignore b/.gitignore
index 7ee06c2c7f..e8a3ef1790 100644
--- a/.gitignore
+++ b/.gitignore
@@ -119,4 +119,5 @@ src/Umbraco.Web.UI.Client/bower_components/*
 /src/Umbraco.Web.UI/Umbraco/preview
 
 #Ignore Rule for output of generated documentation files from Grunt docserve
-src/Umbraco.Web.UI.Client/docs/api
\ No newline at end of file
+src/Umbraco.Web.UI.Client/docs/api
+src/*.boltdata/
diff --git a/src/Umbraco.Core/Models/Rdbms/DataTypePreValueDto.cs b/src/Umbraco.Core/Models/Rdbms/DataTypePreValueDto.cs
index 54f049fef9..ad0b915363 100644
--- a/src/Umbraco.Core/Models/Rdbms/DataTypePreValueDto.cs
+++ b/src/Umbraco.Core/Models/Rdbms/DataTypePreValueDto.cs
@@ -28,5 +28,23 @@ namespace Umbraco.Core.Models.Rdbms
         [NullSetting(NullSetting = NullSettings.Null)]
         [Length(50)]
         public string Alias { get; set; }
+
+        protected bool Equals(DataTypePreValueDto other)
+        {
+            return Id == other.Id;
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (ReferenceEquals(null, obj)) return false;
+            if (ReferenceEquals(this, obj)) return true;
+            if (obj.GetType() != this.GetType()) return false;
+            return Equals((DataTypePreValueDto) obj);
+        }
+
+        public override int GetHashCode()
+        {
+            return Id;
+        }
     }
 }
\ No newline at end of file
diff --git a/src/Umbraco.Core/Persistence/Repositories/VersionableRepositoryBase.cs b/src/Umbraco.Core/Persistence/Repositories/VersionableRepositoryBase.cs
index 6b6b453f48..1c75759f5b 100644
--- a/src/Umbraco.Core/Persistence/Repositories/VersionableRepositoryBase.cs
+++ b/src/Umbraco.Core/Persistence/Repositories/VersionableRepositoryBase.cs
@@ -292,15 +292,18 @@ namespace Umbraco.Core.Persistence.Repositories
                             SortOrder = x.sortorder,
                             Value = x.value
                         })
-                        .ToDictionary(x => x.Alias, x => new PreValue(x.Id, x.Value, x.SortOrder));
+                        .Distinct()
+                        .ToArray();
 
-                    var preVals = new PreValueCollection(preValData);
+                    var asDictionary = preValData.ToDictionary(x => x.Alias, x => new PreValue(x.Id, x.Value, x.SortOrder));
 
-                    var d = new ContentPropertyData(property.Value,
+                    var preVals = new PreValueCollection(asDictionary);
+
+                    var contentPropData = new ContentPropertyData(property.Value,
                         preVals,
                         new Dictionary<string, object>());
 
-                    TagExtractor.SetPropertyTags(property, d, property.Value, tagSupport);
+                    TagExtractor.SetPropertyTags(property, contentPropData, property.Value, tagSupport);
                 }
             }
 
@@ -386,15 +389,18 @@ namespace Umbraco.Core.Persistence.Repositories
                                 SortOrder = x.sortorder,
                                 Value = x.value
                             })
-                            .ToDictionary(x => x.Alias, x => new PreValue(x.Id, x.Value, x.SortOrder));
+                            .Distinct()
+                            .ToArray();
+                            
+                        var asDictionary = preValData.ToDictionary(x => x.Alias, x => new PreValue(x.Id, x.Value, x.SortOrder));
 
-                        var preVals = new PreValueCollection(preValData);
+                        var preVals = new PreValueCollection(asDictionary);
 
-                        var d = new ContentPropertyData(property.Value,
+                        var contentPropData = new ContentPropertyData(property.Value,
                             preVals,
                             new Dictionary<string, object>());
 
-                        TagExtractor.SetPropertyTags(property, d, property.Value, tagSupport);
+                        TagExtractor.SetPropertyTags(property, contentPropData, property.Value, tagSupport);
                     }
                 }