diff --git a/src/MeshModel/MeshModelMetadata.cs b/src/MeshModel/MeshModelMetadata.cs
index 408dc6c..730f9ff 100644
--- a/src/MeshModel/MeshModelMetadata.cs
+++ b/src/MeshModel/MeshModelMetadata.cs
@@ -318,7 +318,7 @@ private static MeshModelMetadata ReadFrom( Stream stream, IGuidGenerator fallbac
 				{
 					case "Guid":
 						result.Guid = Guid.ParseExact( reader.ReadString(), "N" );
-						hasGuid = true;
+						hasGuid = result.Guid != Guid.Empty;
 						break;
 					case "TriangulationHash":
 						result.TriangulationHash = Guid.ParseExact( reader.ReadString(), "N" );