Index: Ringtoets/Integration/src/Ringtoets.Integration.Forms/Views/AssemblyResultTotalView.cs
===================================================================
diff -u -r8e42df9f0d1e647da23c12d02932efe41691a15c -r933d13f37606dd02f49148d8f1c4bb556b1dfbdf
--- Ringtoets/Integration/src/Ringtoets.Integration.Forms/Views/AssemblyResultTotalView.cs	(.../AssemblyResultTotalView.cs)	(revision 8e42df9f0d1e647da23c12d02932efe41691a15c)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Forms/Views/AssemblyResultTotalView.cs	(.../AssemblyResultTotalView.cs)	(revision 933d13f37606dd02f49148d8f1c4bb556b1dfbdf)
@@ -53,9 +53,12 @@
     /// </summary>
     public partial class AssemblyResultTotalView : UserControl, IView
     {
+        private readonly Observer assessmentSectionObserver;
         private readonly Observer assessmentSectionResultObserver;
         private IEnumerable<FailureMechanismAssemblyResultRowBase> assemblyResultRows;
 
+        private bool updateDataSource;
+
         /// <summary>
         /// Creates a new instance of <see cref="AssemblyResultTotalView"/>.
         /// </summary>
@@ -73,6 +76,15 @@
 
             InitializeComponent();
 
+            assessmentSectionObserver = new Observer(() =>
+            {
+                updateDataSource = true;
+                EnableRefreshButton();
+            })
+            {
+                Observable = assessmentSection
+            };
+
             assessmentSectionResultObserver = new Observer(EnableRefreshButton)
             {
                 Observable = new AssessmentSectionResultObserver(assessmentSection)
@@ -98,11 +110,10 @@
 
         protected override void Dispose(bool disposing)
         {
-            dataGridViewControl.CellFormatting -= HandleCellStyling;
-
             if (disposing)
             {
                 components?.Dispose();
+                assessmentSectionObserver.Dispose();
                 assessmentSectionResultObserver.Dispose();
             }
 
@@ -141,10 +152,10 @@
                                                  Resources.AssemblyResultTotalView_Probability_DisplayName,
                                                  true);
 
-            InitializeRows();
+            SetDataSource();
         }
 
-        private void InitializeRows()
+        private void SetDataSource()
         {
             assemblyResultRows = new List<FailureMechanismAssemblyResultRowBase>
             {
@@ -169,15 +180,24 @@
             };
 
             dataGridViewControl.SetDataSource(assemblyResultRows);
+            updateDataSource = false;
         }
 
         private void RefreshAssemblyResults_Click(object sender, EventArgs e)
         {
             refreshAssemblyResultsButton.Enabled = false;
             warningProvider.SetError(refreshAssemblyResultsButton, string.Empty);
 
-            assemblyResultRows.ForEachElementDo(row => row.Update());
-            dataGridViewControl.RefreshDataGridView();
+            if (updateDataSource)
+            {
+                SetDataSource();
+            }
+            else
+            {
+                assemblyResultRows.ForEachElementDo(row => row.Update());
+                dataGridViewControl.RefreshDataGridView();
+            }
+
             UpdateAssemblyResultControls();
         }
 
Index: Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/Views/AssemblyResultTotalViewTest.cs
===================================================================
diff -u -r03a42f53227ba94fae59ac8a103861e201138398 -r933d13f37606dd02f49148d8f1c4bb556b1dfbdf
--- Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/Views/AssemblyResultTotalViewTest.cs	(.../AssemblyResultTotalViewTest.cs)	(revision 03a42f53227ba94fae59ac8a103861e201138398)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/Views/AssemblyResultTotalViewTest.cs	(.../AssemblyResultTotalViewTest.cs)	(revision 933d13f37606dd02f49148d8f1c4bb556b1dfbdf)
@@ -344,6 +344,7 @@
                 var invalidated = false;
                 DataGridView dataGridView = GetDataGridView();
                 dataGridView.Invalidated += (sender, args) => invalidated = true;
+                object dataSource = dataGridView.DataSource;
 
                 // Precondition
                 Assert.IsFalse(invalidated);
@@ -361,7 +362,8 @@
 
                 buttonTester.Click();
 
-                // Then 
+                // Then
+                Assert.AreSame(dataSource, dataGridView.DataSource);
                 Assert.IsTrue(invalidated);
                 AssertFailureMechanismRows(view.AssessmentSection, newAssemblyResult, newCategoryGroup, rows);
             }
@@ -501,6 +503,29 @@
             }
         }
 
+        [Test]
+        [SetCulture("nl-NL")]
+        public void GivenAssessmentSectionObserversNotified_WhenRefreshingAssemblyResults_ThenDataGridViewDataSourceUpdated()
+        {
+            // Given
+            using (new AssemblyToolCalculatorFactoryConfig())
+            using (AssemblyResultTotalView view = ShowAssemblyResultTotalView())
+            {
+                ButtonTester buttonTester = GetRefreshAssemblyResultButtonTester();
+                buttonTester.Properties.Enabled = true;
+
+                DataGridView dataGridView = GetDataGridView();
+                object dataSource = dataGridView.DataSource;
+
+                // When
+                view.AssessmentSection.NotifyObservers();
+                buttonTester.Click();
+
+                // Then
+                Assert.AreNotSame(dataSource, dataGridView.DataSource);
+            }
+        }
+
         #region View test helpers
 
         private AssemblyResultTotalView ShowAssemblyResultTotalView()
@@ -534,7 +559,7 @@
 
         private static FailureMechanismAssemblyControl GetFailureMechanismAssemblyControl()
         {
-            return (FailureMechanismAssemblyControl)new ControlTester(failureMechanismsWithProbabilityControlName).TheObject;
+            return (FailureMechanismAssemblyControl) new ControlTester(failureMechanismsWithProbabilityControlName).TheObject;
         }
 
         private static BorderedLabel GetGroupLabel(AssemblyResultControl control)