Index: Ringtoets/Integration/src/Ringtoets.Integration.IO/Handlers/IHydraulicBoundaryDatabaseUpdateHandler.cs
===================================================================
diff -u -r60449dd57afa878b9deca929461da09da77ab107 -rb67e84a1d4c08afc280f5b0e75ef0f7909873795
--- Ringtoets/Integration/src/Ringtoets.Integration.IO/Handlers/IHydraulicBoundaryDatabaseUpdateHandler.cs	(.../IHydraulicBoundaryDatabaseUpdateHandler.cs)	(revision 60449dd57afa878b9deca929461da09da77ab107)
+++ Ringtoets/Integration/src/Ringtoets.Integration.IO/Handlers/IHydraulicBoundaryDatabaseUpdateHandler.cs	(.../IHydraulicBoundaryDatabaseUpdateHandler.cs)	(revision b67e84a1d4c08afc280f5b0e75ef0f7909873795)
@@ -19,6 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Collections.Generic;
 using Core.Common.Base;
 using Ringtoets.Common.Data.Hydraulics;
@@ -38,6 +39,7 @@
         /// <param name="hydraulicBoundaryDatabase">The hydraulic boundary database.</param>
         /// <param name="readHydraulicBoundaryDatabase">The read hydraulic boundary database.</param>
         /// <returns><c>true</c> when confirmation is required; <c>false</c> otherwise.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
         bool IsConfirmationRequired(HydraulicBoundaryDatabase hydraulicBoundaryDatabase, ReadHydraulicBoundaryDatabase readHydraulicBoundaryDatabase);
 
         /// <summary>
Index: Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Handlers/HydraulicBoundaryDatabaseUpdateHandler.cs
===================================================================
diff -u -rcbe83a33648625a849a8f4afdd28a6d2f9bc4179 -rb67e84a1d4c08afc280f5b0e75ef0f7909873795
--- Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Handlers/HydraulicBoundaryDatabaseUpdateHandler.cs	(.../HydraulicBoundaryDatabaseUpdateHandler.cs)	(revision cbe83a33648625a849a8f4afdd28a6d2f9bc4179)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Plugin/Handlers/HydraulicBoundaryDatabaseUpdateHandler.cs	(.../HydraulicBoundaryDatabaseUpdateHandler.cs)	(revision b67e84a1d4c08afc280f5b0e75ef0f7909873795)
@@ -58,6 +58,16 @@
 
         public bool IsConfirmationRequired(HydraulicBoundaryDatabase hydraulicBoundaryDatabase, ReadHydraulicBoundaryDatabase readHydraulicBoundaryDatabase)
         {
+            if (hydraulicBoundaryDatabase == null)
+            {
+                throw new ArgumentNullException(nameof(hydraulicBoundaryDatabase));
+            }
+
+            if (readHydraulicBoundaryDatabase == null)
+            {
+                throw new ArgumentNullException(nameof(readHydraulicBoundaryDatabase));
+            }
+
             return hydraulicBoundaryDatabase.IsLinked() && hydraulicBoundaryDatabase.Version != readHydraulicBoundaryDatabase.Version;
         }
 
Index: Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Handlers/HydraulicBoundaryDatabaseUpdateHandlerTest.cs
===================================================================
diff -u -rcbe83a33648625a849a8f4afdd28a6d2f9bc4179 -rb67e84a1d4c08afc280f5b0e75ef0f7909873795
--- Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Handlers/HydraulicBoundaryDatabaseUpdateHandlerTest.cs	(.../HydraulicBoundaryDatabaseUpdateHandlerTest.cs)	(revision cbe83a33648625a849a8f4afdd28a6d2f9bc4179)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/Handlers/HydraulicBoundaryDatabaseUpdateHandlerTest.cs	(.../HydraulicBoundaryDatabaseUpdateHandlerTest.cs)	(revision b67e84a1d4c08afc280f5b0e75ef0f7909873795)
@@ -57,6 +57,34 @@
         }
 
         [Test]
+        public void IsConfirmationRequired_HydraulicBoundaryDatabaseNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var handler = new HydraulicBoundaryDatabaseUpdateHandler(new AssessmentSection(AssessmentSectionComposition.Dike));
+
+            // Call
+            TestDelegate call = () => handler.IsConfirmationRequired(null, ReadHydraulicBoundaryDatabaseTestFactory.Create());
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(call);
+            Assert.AreEqual("hydraulicBoundaryDatabase", exception.ParamName);
+        }
+
+        [Test]
+        public void IsConfirmationRequired_ReadHydraulicBoundaryDatabaseNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var handler = new HydraulicBoundaryDatabaseUpdateHandler(new AssessmentSection(AssessmentSectionComposition.Dike));
+
+            // Call
+            TestDelegate call = () => handler.IsConfirmationRequired(new HydraulicBoundaryDatabase(), null);
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(call);
+            Assert.AreEqual("readHydraulicBoundaryDatabase", exception.ParamName);
+        }
+
+        [Test]
         public void IsConfirmationRequired_HydraulicBoundaryDatabaseNotLinked_ReturnsFalse()
         {
             // Setup