Index: Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingCalculationGroupContextTest.cs
===================================================================
diff -u -r3ddd2dfb07fb310dd90d5aac12e213d188c87a9a -r1135c8dff2d97eb3b8f17ada1f96bc068ac06bc2
--- Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingCalculationGroupContextTest.cs	(.../PipingCalculationGroupContextTest.cs)	(revision 3ddd2dfb07fb310dd90d5aac12e213d188c87a9a)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Forms.Test/PresentationObjects/PipingCalculationGroupContextTest.cs	(.../PipingCalculationGroupContextTest.cs)	(revision 1135c8dff2d97eb3b8f17ada1f96bc068ac06bc2)
@@ -19,6 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System.Collections.Generic;
 using NUnit.Framework;
 using Rhino.Mocks;
 using Ringtoets.Common.Data.AssessmentSection;
@@ -156,6 +157,40 @@
         }
 
         [Test]
+        public void Equals_ToDerivedObject_ReturnsFalse()
+        {
+            // Setup
+            var mocks = new MockRepository();
+            var assessmentSection = mocks.Stub<IAssessmentSection>();
+            mocks.ReplayAll();
+
+            var calculationGroup = new CalculationGroup();
+            var parent = new CalculationGroup();
+            var failureMechanism = new PipingFailureMechanism();
+            var surfaceLines = new PipingSurfaceLine[0];
+            var soilModels = new PipingStochasticSoilModel[0];
+            var context = new PipingCalculationGroupContext(calculationGroup,
+                                                            parent,
+                                                            surfaceLines,
+                                                            soilModels,
+                                                            failureMechanism,
+                                                            assessmentSection);
+            var derivedContext = new DerivedPipingCalculationGroupContext(calculationGroup,
+                                                                          parent,
+                                                                          surfaceLines,
+                                                                          soilModels,
+                                                                          failureMechanism,
+                                                                          assessmentSection);
+
+            // Call
+            bool isEqual = context.Equals(derivedContext);
+
+            // Assert
+            Assert.IsFalse(isEqual);
+            mocks.VerifyAll();
+        }
+
+        [Test]
         public void Equals_ToOtherWithDifferentWrappedData_ReturnFalse()
         {
             // Setup
@@ -303,5 +338,16 @@
 
             mocks.VerifyAll();
         }
+
+        private class DerivedPipingCalculationGroupContext : PipingCalculationGroupContext
+        {
+            public DerivedPipingCalculationGroupContext(CalculationGroup calculationGroup,
+                                                        CalculationGroup parent,
+                                                        IEnumerable<PipingSurfaceLine> surfaceLines,
+                                                        IEnumerable<PipingStochasticSoilModel> stochasticSoilModels,
+                                                        PipingFailureMechanism pipingFailureMechanism,
+                                                        IAssessmentSection assessmentSection)
+                : base(calculationGroup, parent, surfaceLines, stochasticSoilModels, pipingFailureMechanism, assessmentSection) {}
+        }
     }
 }
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