Index: Ringtoets/Piping/src/Ringtoets.Piping.Forms/PresentationObjects/PipingCalculationGroupContext.cs
===================================================================
diff -u -r26f527fb809a2325c8f883ece9da01a8f8040eb3 -r3ddd2dfb07fb310dd90d5aac12e213d188c87a9a
--- Ringtoets/Piping/src/Ringtoets.Piping.Forms/PresentationObjects/PipingCalculationGroupContext.cs	(.../PipingCalculationGroupContext.cs)	(revision 26f527fb809a2325c8f883ece9da01a8f8040eb3)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Forms/PresentationObjects/PipingCalculationGroupContext.cs	(.../PipingCalculationGroupContext.cs)	(revision 3ddd2dfb07fb310dd90d5aac12e213d188c87a9a)
@@ -21,6 +21,7 @@
 
 using System;
 using System.Collections.Generic;
+using Core.Common.Controls.PresentationObjects;
 using Ringtoets.Common.Data.AssessmentSection;
 using Ringtoets.Common.Data.Calculation;
 using Ringtoets.Common.Forms.PresentationObjects;
@@ -59,5 +60,22 @@
         }
 
         public CalculationGroup Parent { get; }
+
+        public override bool Equals(WrappedObjectContextBase<CalculationGroup> other)
+        {
+            return base.Equals(other)
+                   && other is PipingCalculationGroupContext
+                   && ReferenceEquals(Parent, ((PipingCalculationGroupContext) other).Parent);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return Equals(obj as PipingCalculationGroupContext);
+        }
+
+        public override int GetHashCode()
+        {
+            return base.GetHashCode() ^ Parent.GetHashCode();
+        }
     }
 }
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