Index: Core/Common/test/Core.Common.Base.Test/Service/FileImportActivityTest.cs
===================================================================
diff -u -r81982c798fc50dab94c8f1eb8799c04242515564 -rd2d92ca3de81331e4fc6766c23f8fea45fd6cc81
--- Core/Common/test/Core.Common.Base.Test/Service/FileImportActivityTest.cs	(.../FileImportActivityTest.cs)	(revision 81982c798fc50dab94c8f1eb8799c04242515564)
+++ Core/Common/test/Core.Common.Base.Test/Service/FileImportActivityTest.cs	(.../FileImportActivityTest.cs)	(revision d2d92ca3de81331e4fc6766c23f8fea45fd6cc81)
@@ -138,15 +138,20 @@
         }
 
         [Test]
-        public void Finish_FileImportActivityWithFileImporter_NoLogicPerformed()
+        public void Finish_FileImportActivityWithFileImporterAndObservableTarget_ObserversOfTargetAreNotified()
         {
             // Setup
             var mocks = new MockRepository();
             var fileImporter = mocks.Stub<IFileImporter>();
-            var target = new object();
+            var observer = mocks.StrictMock<IObserver>();
 
+            observer.Expect(o => o.UpdateObserver());
+
             mocks.ReplayAll();
 
+            var target = new ObservableList<object>();
+            target.Attach(observer);
+
             var fileImportActivity = new FileImportActivity(fileImporter, target, "");
 
             // Call
Index: Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSoilProfilesImporterTest.cs
===================================================================
diff -u -r654d3a712eedbdeea718dc0448c5544f09e053cd -rd2d92ca3de81331e4fc6766c23f8fea45fd6cc81
--- Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSoilProfilesImporterTest.cs	(.../PipingSoilProfilesImporterTest.cs)	(revision 654d3a712eedbdeea718dc0448c5544f09e053cd)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSoilProfilesImporterTest.cs	(.../PipingSoilProfilesImporterTest.cs)	(revision d2d92ca3de81331e4fc6766c23f8fea45fd6cc81)
@@ -272,7 +272,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var importer = new PipingSoilProfilesImporter
@@ -301,7 +300,7 @@
             Assert.AreEqual(1, observableSoilProfileList.Count);
             Assert.AreEqual(4, progress);
 
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
 
         [Test]
@@ -312,7 +311,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var importer = new PipingSoilProfilesImporter
@@ -329,7 +327,7 @@
             Assert.IsTrue(importResult);
             Assert.AreEqual(0, observableSoilProfileList.Count);
 
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
 
         private void IncrementProgress(string a, int b, int c)
Index: Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSurfaceLineCsvImporterTest.cs
===================================================================
diff -u -r654d3a712eedbdeea718dc0448c5544f09e053cd -rd2d92ca3de81331e4fc6766c23f8fea45fd6cc81
--- Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSurfaceLineCsvImporterTest.cs	(.../PipingSurfaceLineCsvImporterTest.cs)	(revision 654d3a712eedbdeea718dc0448c5544f09e053cd)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Plugin.Test/FileImporter/PipingSurfaceLineCsvImporterTest.cs	(.../PipingSurfaceLineCsvImporterTest.cs)	(revision d2d92ca3de81331e4fc6766c23f8fea45fd6cc81)
@@ -52,7 +52,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var observableSurfaceLinesList = new ObservableList<RingtoetsPipingSurfaceLine>();
@@ -106,7 +105,7 @@
 
             Assert.IsTrue(TestHelper.CanOpenFileForWrite(validFilePath));
 
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
 
         [Test]
@@ -118,7 +117,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var observableSurfaceLinesList = new ObservableList<RingtoetsPipingSurfaceLine>();
@@ -154,7 +152,7 @@
 
             Assert.IsTrue(TestHelper.CanOpenFileForWrite(validFilePath));
 
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
 
         [Test]
@@ -413,7 +411,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var importer = new PipingSurfaceLinesCsvImporter();
@@ -445,7 +442,7 @@
 
             Assert.AreEqual(5, progressCallCount,
                             "Expect 1 call for each surfaceline (3 in total) +1 for 0/N progress, and 1 for putting data in model.");
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
 
         [Test]
@@ -457,7 +454,6 @@
 
             var mocks = new MockRepository();
             var observer = mocks.StrictMock<IObserver>();
-            observer.Expect(o => o.UpdateObserver());
             mocks.ReplayAll();
 
             var observableSurfaceLinesList = new ObservableList<RingtoetsPipingSurfaceLine>();
@@ -487,7 +483,7 @@
 
             Assert.IsTrue(TestHelper.CanOpenFileForWrite(path));
 
-            mocks.VerifyAll();
+            mocks.VerifyAll(); // Ensure there are no calls to UpdateObserver
         }
     }
 }
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