Index: Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/MacroStabilityInwardsSurfaceLine.cs
===================================================================
diff -u -r66396d7a91ffdfadfcd6a94759ce579c611c78b9 -rff0911662b90e32ee3f34444ae6b33b91f6cc85d
--- Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/MacroStabilityInwardsSurfaceLine.cs	(.../MacroStabilityInwardsSurfaceLine.cs)	(revision 66396d7a91ffdfadfcd6a94759ce579c611c78b9)
+++ Ringtoets/MacroStabilityInwards/src/Ringtoets.MacroStabilityInwards.Primitives/MacroStabilityInwardsSurfaceLine.cs	(.../MacroStabilityInwardsSurfaceLine.cs)	(revision ff0911662b90e32ee3f34444ae6b33b91f6cc85d)
@@ -349,8 +349,7 @@
             {
                 return true;
             }
-            var other = obj as MacroStabilityInwardsSurfaceLine;
-            return other != null && Equals((MacroStabilityInwardsSurfaceLine) obj);
+            return GetType() == obj.GetType() && Equals((MacroStabilityInwardsSurfaceLine) obj);
         }
 
         public override int GetHashCode()