diff --git a/src/coreclr/vm/methodtablebuilder.cpp b/src/coreclr/vm/methodtablebuilder.cpp
index 3f58e50ca303df..06cede08de1f64 100644
--- a/src/coreclr/vm/methodtablebuilder.cpp
+++ b/src/coreclr/vm/methodtablebuilder.cpp
@@ -9833,13 +9833,22 @@ MethodTableBuilder::LoadExactInterfaceMap(MethodTable *pMT)
                     {
                         MethodTable *pItfPossiblyApprox = intIt.GetInterfaceApprox();
 
-                        // pItfPossiblyApprox can be in 4 situations
+                        // pItfPossiblyApprox can be in 6 situations
                         // 1. It has no instantiation
-                        // 2. It is a special marker type, AND pNewItfMT is a special marker type. Compute the exact instantiation as containing entirely a list of types corresponding to calling GetSpecialInstantiationType on pMT (This rule works based on the current behavior of GetSpecialInstantiationType where it treats all interfaces the same)
-                        // 3. It is a special marker type, but pNewItfMT is NOT a special marker type. Compute the exact instantiation as containing entirely a list of types corresponding to calling GetSpecialInstantiationType on pNewItfMT
-                        // 4. It is an exact instantiation
+                        // 2. It is a special marker type, AND pNewIntfMT is a special marker type. Compute the exact instantiation as containing entirely a list of
+                        //    types corresponding to calling GetSpecialInstantiationType on pMT (This rule works based on the current behavior of
+                        //    GetSpecialInstantiationType where it treats all interfaces the same)
+                        // 3. It is a special marker type, but pNewIntfMT is NOT a special marker type. Compute the exact instantiation as containing entirely a list
+                        //    of types corresponding to calling GetSpecialInstantiationType on pNewIntfMT
+                        // 4. It is an exact instantiation, but pNewIntfMT was a special marker type, and the exact instantiation type found here could have been a
+                        //    special marker type. This should produce a result equivalent to case 2 (the special marker type)
+                        // 5. It is an exact instantiation, but pNewIntfMT was a special marker type, and the exact instantiation type is NOT one which would have
+                        //    been on the exact instantiation of pNewIntfMT if it were not a special marker type. In theory we could reconstruct this, but this is a
+                        //    rare scenario, so we just fallback to the retry with exact interfaces pathway
+                        // 6. It is an exact instantiation, and pNewIntfMT is NOT a special marker type, compute the result and insert either a special marker or
+                        //    the exact instantiation already found.
                         //
-                        // NOTE: pItfPossiblyApprox must not be considered a special marker type if pNewItfMT has the MayHaveOpenInterfacesInInterfaceMap flag set
+                        // NOTE: pItfPossiblyApprox must not be considered a special marker type if pNewIntfMT has the MayHaveOpenInterfacesInInterfaceMap flag set
                         //
                         // Then determine if all of the following conditions hold true.
                         // 1. All generic arguments are the same (always true for cases 2 and 3 above)
@@ -9889,17 +9898,40 @@ MethodTableBuilder::LoadExactInterfaceMap(MethodTable *pMT)
                         }
                         else
                         {
-                            // case 4 (We have an exact interface)
-                            if (ClassLoader::EligibleForSpecialMarkerTypeUsage(pItfPossiblyApprox->GetInstantiation(), pMT))
+                            // case 4, 5, or 6 (We have an exact interface)
+                            bool pNewIntfMTIsSpecialMarkerType = pNewIntfMT->IsSpecialMarkerTypeForGenericCasting() && !pMT->GetAuxiliaryData()->MayHaveOpenInterfacesInInterfaceMap();
+                            if (pNewIntfMTIsSpecialMarkerType)
                             {
-                                // Validated that all generic arguments are the same, and that the first generic argument in the instantiation is exactly the value of calling GetSpecialInstantiationType on pMT
-                                // Then use the special marker type here
-                                pItfToInsert = ClassLoader::LoadTypeDefThrowing(pItfPossiblyApprox->GetModule(), pItfPossiblyApprox->GetCl(), ClassLoader::ThrowIfNotFound, ClassLoader::PermitUninstDefOrRef, 0, CLASS_LOAD_EXACTPARENTS).AsMethodTable();
+                                if (ClassLoader::EligibleForSpecialMarkerTypeUsage(pItfPossiblyApprox->GetInstantiation(), pNewIntfMT))
+                                {
+                                    // Case 4 - we have an exact instantiation, but pNewIntfMT was a special marker type, and the exact instantiation type found here could have been a special marker type. We need to check if the exact instantiation we found
+                                    // here could have been a special marker type. If it is, we need to insert the special marker type here.
+                                    pItfToInsert = ClassLoader::LoadTypeDefThrowing(pItfPossiblyApprox->GetModule(), pItfPossiblyApprox->GetCl(), ClassLoader::ThrowIfNotFound, ClassLoader::PermitUninstDefOrRef, 0, CLASS_LOAD_EXACTPARENTS).AsMethodTable();
+                                }
+                                else if (pItfPossiblyApprox->ContainsGenericVariables())
+                                {
+                                    // Case 5
+                                    // If the instantiation contains generic variables and can't be converted to the special marker type, then we would need to fully re-instantiate the type with a deep substitution to get the exact instantiation, which is complex and expensive, and we expect this to be a rare case, so we can just fallback to the retry with exact interfaces pathway in this case.
+                                    retry = true;
+                                    break;
+                                }
+                                // If we reach here, we've already found the correct pItfToInsert (case 4), OR we can proceed to case 6 since pItfPossiblyApprox was an exact type defined on the generic type.
                             }
-                            else
+
+                            if (pItfToInsert == NULL)
                             {
-                                pItfToInsert = pItfPossiblyApprox;
-                                intendedExactMatch = true;
+                                // Case 6, this is an exact instantiation of exactly the right type. Insert it here.
+                                if (ClassLoader::EligibleForSpecialMarkerTypeUsage(pItfPossiblyApprox->GetInstantiation(), pMT))
+                                {
+                                    // Validated that all generic arguments are the same, and that the first generic argument in the instantiation is exactly the value of calling GetSpecialInstantiationType on pMT
+                                    // Then use the special marker type here
+                                    pItfToInsert = ClassLoader::LoadTypeDefThrowing(pItfPossiblyApprox->GetModule(), pItfPossiblyApprox->GetCl(), ClassLoader::ThrowIfNotFound, ClassLoader::PermitUninstDefOrRef, 0, CLASS_LOAD_EXACTPARENTS).AsMethodTable();
+                                }
+                                else
+                                {
+                                    pItfToInsert = pItfPossiblyApprox;
+                                    intendedExactMatch = true;
+                                }
                             }
                         }
 
diff --git a/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vb b/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vb
new file mode 100644
index 00000000000000..a3dcb0cfbb3c54
--- /dev/null
+++ b/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vb
@@ -0,0 +1,1440 @@
+' Licensed to the .NET Foundation under one or more agreements.
+' The .NET Foundation licenses this file to you under the MIT license.
+
+Imports System
+Imports System.Collections
+Imports System.Collections.Generic
+Imports Xunit
+Imports System.Runtime.CompilerServices
+
+' This test needs to be written in VB, since the C# compiler has a different rule around
+' filling in the InterfaceImpl table. Notably, the C# compiler will emit into the table, all of the
+' interfaces that are transitively implemented by a class that the C# compiler is aware of, and
+' the VB compiler will only emit the interfaces as specified in the source. In practice, this isn't
+' supposed to have any meaningful impact unless the set of assemblies being used at runtime does not
+' match the set of assemblies used at compile time, but it does impact some of the runtimes internal
+' algorithms around interface resolution, notably the behavior of LoadExactInterfaceMap has an optimization
+' that avoids doing quite a lot of work.
+'
+' This is a variant of GitHub_123254 test which tests the situations where various of the interfaces
+' types have had their open generic type loaded, and the interfaces examined
+Public Class GitHub_124369
+
+    ' Test the scenario where the implied interface is in the interface map of a containing interface as a special marker type, and the containing interface itself is ALSO a special marker type.
+    ' The critical path is that when establishing the interface map for ILayer3_1(Of T) we find read ILayer1_1(Of T) as a special marker type member of ILayer2_1(Of T), and the ILayer2_1(Of T) itself is a special marker type.
+    <Fact>
+    Public Shared Sub Test_Method1_000()
+        Test_Method1_000_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_000_Inner()
+        Dim w As New TestClass1_000(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_000(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_000(Of T)
+        Implements ILayer3_1_000(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_000(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_000(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_000(Of T)
+        Inherits ILayer2_1_000(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_000(Of T)
+        Inherits ILayer1_1_000(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_000(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_001()
+        GetType(ILayer3_1_001(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_001_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_001_Inner()
+        Dim w As New TestClass1_001(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_001(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_001(Of T)
+        Implements ILayer3_1_001(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_001(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_001(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_001(Of T)
+        Inherits ILayer2_1_001(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_001(Of T)
+        Inherits ILayer1_1_001(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_001(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_010()
+        GetType(ILayer2_1_010(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_010_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_010_Inner()
+        Dim w As New TestClass1_010(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_010(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_010(Of T)
+        Implements ILayer3_1_010(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_010(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_010(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_010(Of T)
+        Inherits ILayer2_1_010(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_010(Of T)
+        Inherits ILayer1_1_010(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_010(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_011()
+        GetType(ILayer2_1_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_1_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_011_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_011_Inner()
+        Dim w As New TestClass1_011(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_011(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_011(Of T)
+        Implements ILayer3_1_011(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_011(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_011(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_011(Of T)
+        Inherits ILayer2_1_011(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_011(Of T)
+        Inherits ILayer1_1_011(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_011(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_100()
+        GetType(ILayer1_1_100(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_100_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_100_Inner()
+        Dim w As New TestClass1_100(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_100(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_100(Of T)
+        Implements ILayer3_1_100(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_100(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_100(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_100(Of T)
+        Inherits ILayer2_1_100(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_100(Of T)
+        Inherits ILayer1_1_100(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_100(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_101()
+        GetType(ILayer1_1_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_1_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_101_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_101_Inner()
+        Dim w As New TestClass1_101(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_101(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_101(Of T)
+        Implements ILayer3_1_101(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_101(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_101(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_101(Of T)
+        Inherits ILayer2_1_101(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_101(Of T)
+        Inherits ILayer1_1_101(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_101(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_110()
+        GetType(ILayer1_1_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_1_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_110_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_110_Inner()
+        Dim w As New TestClass1_110(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_110(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_110(Of T)
+        Implements ILayer3_1_110(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_110(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_110(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_110(Of T)
+        Inherits ILayer2_1_110(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_110(Of T)
+        Inherits ILayer1_1_110(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_110(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method1_111()
+        GetType(ILayer1_1_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_1_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_1_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method1_111_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method1_111_Inner()
+        Dim w As New TestClass1_111(Of Integer)
+        Dim en As IEnumerator(Of Integer) = DirectCast(w, ILayer1_1_111(Of Integer)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass1_111(Of T)
+        Implements ILayer3_1_111(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_1_111(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of T) Implements ILayer1_1_111(Of T).GetEnumerator
+            Return DirectCast(Array.Empty(Of T)(), IEnumerable(Of T)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_1_111(Of T)
+        Inherits ILayer2_1_111(Of T)
+    End Interface
+
+    Public Interface ILayer2_1_111(Of T)
+        Inherits ILayer1_1_111(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_1_111(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    ' Test the scenario where the implied interface is in the interface map of a containing interface as a special marker type, and the containing interface itself is NOT a special marker type.
+    ' The critical path is that when establishing the interface map for ILayer3_2(Of T) we find read ILayer1_2(Of T) as a special marker type member of ILayer2_2(Of T), and the ILayer2_2(Of T) itself is a special marker type.
+    ' Then, it will also turn out that even though we had a special marker type in the interface map we're expanding, we will need to put an exact type into the map since that's what we actually need.
+    <Fact>
+    Public Shared Sub Test_Method2_000()
+        Test_Method2_000_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_000_Inner()
+        Dim w As New TestClass2_000(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_000(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_000(Of T)
+        Implements ILayer3_2_000(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_000(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_000(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_000(Of T)
+        Inherits ILayer2_2_000(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_000(Of T)
+        Inherits ILayer1_2_000(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_000(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_001()
+        GetType(ILayer3_2_001(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_001_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_001_Inner()
+        Dim w As New TestClass2_001(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_001(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_001(Of T)
+        Implements ILayer3_2_001(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_001(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_001(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_001(Of T)
+        Inherits ILayer2_2_001(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_001(Of T)
+        Inherits ILayer1_2_001(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_001(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_010()
+        GetType(ILayer2_2_010(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_010_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_010_Inner()
+        Dim w As New TestClass2_010(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_010(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_010(Of T)
+        Implements ILayer3_2_010(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_010(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_010(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_010(Of T)
+        Inherits ILayer2_2_010(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_010(Of T)
+        Inherits ILayer1_2_010(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_010(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_011()
+        GetType(ILayer2_2_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_2_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_011_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_011_Inner()
+        Dim w As New TestClass2_011(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_011(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_011(Of T)
+        Implements ILayer3_2_011(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_011(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_011(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_011(Of T)
+        Inherits ILayer2_2_011(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_011(Of T)
+        Inherits ILayer1_2_011(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_011(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_100()
+        GetType(ILayer1_2_100(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_100_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_100_Inner()
+        Dim w As New TestClass2_100(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_100(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_100(Of T)
+        Implements ILayer3_2_100(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_100(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_100(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_100(Of T)
+        Inherits ILayer2_2_100(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_100(Of T)
+        Inherits ILayer1_2_100(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_100(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_101()
+        GetType(ILayer1_2_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_2_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_101_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_101_Inner()
+        Dim w As New TestClass2_101(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_101(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_101(Of T)
+        Implements ILayer3_2_101(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_101(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_101(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_101(Of T)
+        Inherits ILayer2_2_101(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_101(Of T)
+        Inherits ILayer1_2_101(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_101(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_110()
+        GetType(ILayer1_2_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_2_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_110_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_110_Inner()
+        Dim w As New TestClass2_110(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_110(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_110(Of T)
+        Implements ILayer3_2_110(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_110(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_110(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_110(Of T)
+        Inherits ILayer2_2_110(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_110(Of T)
+        Inherits ILayer1_2_110(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_110(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method2_111()
+        GetType(ILayer1_2_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_2_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_2_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method2_111_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method2_111_Inner()
+        Dim w As New TestClass2_111(Of Integer)
+        Dim en As IEnumerator(Of String) = DirectCast(w, ILayer1_2_111(Of String)).GetEnumerator()
+    End Sub
+
+    Public Class TestClass2_111(Of T)
+        Implements ILayer3_2_111(Of T)
+        Public ReadOnly Property Count As Integer Implements ILayer2_2_111(Of String).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of String) Implements ILayer1_2_111(Of String).GetEnumerator
+            Return DirectCast(Array.Empty(Of String)(), IEnumerable(Of String)).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_2_111(Of T)
+        Inherits ILayer2_2_111(Of String)
+    End Interface
+
+    Public Interface ILayer2_2_111(Of T)
+        Inherits ILayer1_2_111(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_2_111(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    ' Test the scenario where the implied interface is in the interface map of a containing interface as a special marker type, and the containing interface itself is NOT a special marker type.
+    ' The critical path is that when establishing the interface map for TestClass3 we find read ILayer1_3(Of T) as a special marker type member of ILayer3_3(Of TestClass, Integer), but when we place
+    ' the interface onto TestClass3 we find that we can use the special marker type even though the containing interface is not the special marker type.
+    <Fact>
+    Public Shared Sub Test_Method3_000()
+        Test_Method3_000_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_000_Inner()
+        Dim w As New TestClass3_000
+        Dim en As IEnumerator(Of TestClass3_000) = DirectCast(w, ILayer1_3_000(Of TestClass3_000)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_000
+        Implements ILayer3_3_000(Of TestClass3_000, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_000(Of TestClass3_000).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_000) Implements ILayer1_3_000(Of TestClass3_000).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_000)(), IEnumerable(Of TestClass3_000)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_000(Of T, SomethingElse)
+        Inherits ILayer2_3_000(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_000(Of T)
+        Inherits ILayer1_3_000(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_000(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_001()
+        GetType(ILayer3_3_001(Of Integer, Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_001_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_001_Inner()
+        Dim w As New TestClass3_001
+        Dim en As IEnumerator(Of TestClass3_001) = DirectCast(w, ILayer1_3_001(Of TestClass3_001)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_001
+        Implements ILayer3_3_001(Of TestClass3_001, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_001(Of TestClass3_001).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_001) Implements ILayer1_3_001(Of TestClass3_001).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_001)(), IEnumerable(Of TestClass3_001)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_001(Of T, SomethingElse)
+        Inherits ILayer2_3_001(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_001(Of T)
+        Inherits ILayer1_3_001(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_001(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_010()
+        GetType(ILayer2_3_010(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_010_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_010_Inner()
+        Dim w As New TestClass3_010
+        Dim en As IEnumerator(Of TestClass3_010) = DirectCast(w, ILayer1_3_010(Of TestClass3_010)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_010
+        Implements ILayer3_3_010(Of TestClass3_010, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_010(Of TestClass3_010).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_010) Implements ILayer1_3_010(Of TestClass3_010).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_010)(), IEnumerable(Of TestClass3_010)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_010(Of T, SomethingElse)
+        Inherits ILayer2_3_010(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_010(Of T)
+        Inherits ILayer1_3_010(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_010(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_011()
+        GetType(ILayer2_3_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_3_011(Of Integer, Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_011_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_011_Inner()
+        Dim w As New TestClass3_011
+        Dim en As IEnumerator(Of TestClass3_011) = DirectCast(w, ILayer1_3_011(Of TestClass3_011)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_011
+        Implements ILayer3_3_011(Of TestClass3_011, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_011(Of TestClass3_011).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_011) Implements ILayer1_3_011(Of TestClass3_011).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_011)(), IEnumerable(Of TestClass3_011)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_011(Of T, SomethingElse)
+        Inherits ILayer2_3_011(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_011(Of T)
+        Inherits ILayer1_3_011(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_011(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_100()
+        GetType(ILayer1_3_100(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_100_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_100_Inner()
+        Dim w As New TestClass3_100
+        Dim en As IEnumerator(Of TestClass3_100) = DirectCast(w, ILayer1_3_100(Of TestClass3_100)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_100
+        Implements ILayer3_3_100(Of TestClass3_100, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_100(Of TestClass3_100).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_100) Implements ILayer1_3_100(Of TestClass3_100).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_100)(), IEnumerable(Of TestClass3_100)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_100(Of T, SomethingElse)
+        Inherits ILayer2_3_100(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_100(Of T)
+        Inherits ILayer1_3_100(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_100(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_101()
+        GetType(ILayer1_3_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_3_101(Of Integer, Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_101_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_101_Inner()
+        Dim w As New TestClass3_101
+        Dim en As IEnumerator(Of TestClass3_101) = DirectCast(w, ILayer1_3_101(Of TestClass3_101)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_101
+        Implements ILayer3_3_101(Of TestClass3_101, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_101(Of TestClass3_101).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_101) Implements ILayer1_3_101(Of TestClass3_101).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_101)(), IEnumerable(Of TestClass3_101)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_101(Of T, SomethingElse)
+        Inherits ILayer2_3_101(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_101(Of T)
+        Inherits ILayer1_3_101(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_101(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_110()
+        GetType(ILayer1_3_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_3_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_110_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_110_Inner()
+        Dim w As New TestClass3_110
+        Dim en As IEnumerator(Of TestClass3_110) = DirectCast(w, ILayer1_3_110(Of TestClass3_110)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_110
+        Implements ILayer3_3_110(Of TestClass3_110, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_110(Of TestClass3_110).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_110) Implements ILayer1_3_110(Of TestClass3_110).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_110)(), IEnumerable(Of TestClass3_110)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_110(Of T, SomethingElse)
+        Inherits ILayer2_3_110(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_110(Of T)
+        Inherits ILayer1_3_110(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_110(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method3_111()
+        GetType(ILayer1_3_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_3_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_3_111(Of Integer, Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method3_111_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method3_111_Inner()
+        Dim w As New TestClass3_111
+        Dim en As IEnumerator(Of TestClass3_111) = DirectCast(w, ILayer1_3_111(Of TestClass3_111)).GetEnumerator()
+    End Sub
+
+    Public Structure TestClass3_111
+        Implements ILayer3_3_111(Of TestClass3_111, Integer)
+        Public ReadOnly Property Count As Integer Implements ILayer2_3_111(Of TestClass3_111).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass3_111) Implements ILayer1_3_111(Of TestClass3_111).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass3_111)(), IEnumerable(Of TestClass3_111)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_3_111(Of T, SomethingElse)
+        Inherits ILayer2_3_111(Of T)
+    End Interface
+
+    Public Interface ILayer2_3_111(Of T)
+        Inherits ILayer1_3_111(Of T)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_3_111(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    ' Test the scenario where the implied interface is in the interface map of a containing interface as a special marker type, and the containing interface itself is NOT a special marker type.
+    ' The critical path is that when establishing the interface map for TestClass4 we find read ILayer3_4(Of String) and then under that there are exact types ILayer2_4(Of Integer) and ILayer1_4(Of TestClass4)
+    ' Then the algorithm will decide to put a special marker type for ILayer1_4(Of T) into the map since it is the appropriate shape, and we will place the exact type ILayer2_4(Of Integer) into the map since that is the exact type needed.
+    <Fact>
+    Public Shared Sub Test_Method4_000()
+        Test_Method4_000_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_000_Inner()
+        Dim w As New TestClass4_000
+        Dim en As IEnumerator(Of TestClass4_000) = DirectCast(w, ILayer1_4_000(Of TestClass4_000)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_000(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_000
+        Implements ILayer3_4_000(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_000(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_000) Implements ILayer1_4_000(Of TestClass4_000).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_000)(), IEnumerable(Of TestClass4_000)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_000(Of T)
+        Inherits ILayer2_4_000(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_000(Of T)
+        Inherits ILayer1_4_000(Of TestClass4_000)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_000(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_001()
+        GetType(ILayer3_4_001(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_001_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_001_Inner()
+        Dim w As New TestClass4_001
+        Dim en As IEnumerator(Of TestClass4_001) = DirectCast(w, ILayer1_4_001(Of TestClass4_001)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_001(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_001
+        Implements ILayer3_4_001(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_001(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_001) Implements ILayer1_4_001(Of TestClass4_001).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_001)(), IEnumerable(Of TestClass4_001)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_001(Of T)
+        Inherits ILayer2_4_001(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_001(Of T)
+        Inherits ILayer1_4_001(Of TestClass4_001)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_001(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_010()
+        GetType(ILayer2_4_010(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_010_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_010_Inner()
+        Dim w As New TestClass4_010
+        Dim en As IEnumerator(Of TestClass4_010) = DirectCast(w, ILayer1_4_010(Of TestClass4_010)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_010(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_010
+        Implements ILayer3_4_010(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_010(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_010) Implements ILayer1_4_010(Of TestClass4_010).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_010)(), IEnumerable(Of TestClass4_010)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_010(Of T)
+        Inherits ILayer2_4_010(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_010(Of T)
+        Inherits ILayer1_4_010(Of TestClass4_010)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_010(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_011()
+        GetType(ILayer2_4_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_4_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_011_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_011_Inner()
+        Dim w As New TestClass4_011
+        Dim en As IEnumerator(Of TestClass4_011) = DirectCast(w, ILayer1_4_011(Of TestClass4_011)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_011(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_011
+        Implements ILayer3_4_011(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_011(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_011) Implements ILayer1_4_011(Of TestClass4_011).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_011)(), IEnumerable(Of TestClass4_011)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_011(Of T)
+        Inherits ILayer2_4_011(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_011(Of T)
+        Inherits ILayer1_4_011(Of TestClass4_011)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_011(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_100()
+        GetType(ILayer1_4_100(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_100_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_100_Inner()
+        Dim w As New TestClass4_100
+        Dim en As IEnumerator(Of TestClass4_100) = DirectCast(w, ILayer1_4_100(Of TestClass4_100)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_100(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_100
+        Implements ILayer3_4_100(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_100(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_100) Implements ILayer1_4_100(Of TestClass4_100).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_100)(), IEnumerable(Of TestClass4_100)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_100(Of T)
+        Inherits ILayer2_4_100(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_100(Of T)
+        Inherits ILayer1_4_100(Of TestClass4_100)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_100(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_101()
+        GetType(ILayer1_4_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_4_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_101_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_101_Inner()
+        Dim w As New TestClass4_101
+        Dim en As IEnumerator(Of TestClass4_101) = DirectCast(w, ILayer1_4_101(Of TestClass4_101)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_101(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_101
+        Implements ILayer3_4_101(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_101(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_101) Implements ILayer1_4_101(Of TestClass4_101).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_101)(), IEnumerable(Of TestClass4_101)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_101(Of T)
+        Inherits ILayer2_4_101(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_101(Of T)
+        Inherits ILayer1_4_101(Of TestClass4_101)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_101(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_110()
+        GetType(ILayer1_4_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_4_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_110_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_110_Inner()
+        Dim w As New TestClass4_110
+        Dim en As IEnumerator(Of TestClass4_110) = DirectCast(w, ILayer1_4_110(Of TestClass4_110)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_110(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_110
+        Implements ILayer3_4_110(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_110(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_110) Implements ILayer1_4_110(Of TestClass4_110).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_110)(), IEnumerable(Of TestClass4_110)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_110(Of T)
+        Inherits ILayer2_4_110(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_110(Of T)
+        Inherits ILayer1_4_110(Of TestClass4_110)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_110(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method4_111()
+        GetType(ILayer1_4_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_4_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_4_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method4_111_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method4_111_Inner()
+        Dim w As New TestClass4_111
+        Dim en As IEnumerator(Of TestClass4_111) = DirectCast(w, ILayer1_4_111(Of TestClass4_111)).GetEnumerator()
+        Dim countVal As Integer = DirectCast(w, ILayer2_4_111(Of Integer)).Count
+    End Sub
+
+    Public Structure TestClass4_111
+        Implements ILayer3_4_111(Of String)
+        Public ReadOnly Property Count As Integer Implements ILayer2_4_111(Of Integer).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of TestClass4_111) Implements ILayer1_4_111(Of TestClass4_111).GetEnumerator
+            Return DirectCast(Array.Empty(Of TestClass4_111)(), IEnumerable(Of TestClass4_111)).GetEnumerator()
+        End Function
+    End Structure
+
+    Public Interface ILayer3_4_111(Of T)
+        Inherits ILayer2_4_111(Of Integer)
+    End Interface
+
+    Public Interface ILayer2_4_111(Of T)
+        Inherits ILayer1_4_111(Of TestClass4_111)
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_4_111(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    ' Test the scenario where the implied interface is in the interface map of a containing interface as a special marker type, and the containing interface itself is ALSO a special marker type.
+    ' The critical path is that when establishing the interface map for ILayer3_1(Of T) we find ILayer1_1(Of IList(Of T)) as an exact instantiation, and are able to identify that it is a problematic scenario which requires us to stop using all of the special marker type logic
+    <Fact>
+    Public Shared Sub Test_Method5_000()
+        Test_Method5_000_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_000_Inner()
+        Dim w As New TestClass5_000(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_000(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_000(Of T)
+        Implements ILayer3_5_000(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_000(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_000(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_000(Of T)
+        Inherits ILayer2_5_000(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_000(Of T)
+        Inherits ILayer1_5_000(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_000(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_001()
+        GetType(ILayer3_5_001(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_001_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_001_Inner()
+        Dim w As New TestClass5_001(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_001(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_001(Of T)
+        Implements ILayer3_5_001(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_001(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_001(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_001(Of T)
+        Inherits ILayer2_5_001(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_001(Of T)
+        Inherits ILayer1_5_001(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_001(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_010()
+        GetType(ILayer2_5_010(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_010_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_010_Inner()
+        Dim w As New TestClass5_010(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_010(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_010(Of T)
+        Implements ILayer3_5_010(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_010(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_010(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_010(Of T)
+        Inherits ILayer2_5_010(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_010(Of T)
+        Inherits ILayer1_5_010(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_010(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_011()
+        GetType(ILayer2_5_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_5_011(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_011_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_011_Inner()
+        Dim w As New TestClass5_011(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_011(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_011(Of T)
+        Implements ILayer3_5_011(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_011(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_011(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_011(Of T)
+        Inherits ILayer2_5_011(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_011(Of T)
+        Inherits ILayer1_5_011(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_011(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_100()
+        GetType(ILayer1_5_100(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_100_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_100_Inner()
+        Dim w As New TestClass5_100(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_100(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_100(Of T)
+        Implements ILayer3_5_100(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_100(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_100(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_100(Of T)
+        Inherits ILayer2_5_100(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_100(Of T)
+        Inherits ILayer1_5_100(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_100(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_101()
+        GetType(ILayer1_5_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_5_101(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_101_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_101_Inner()
+        Dim w As New TestClass5_101(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_101(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_101(Of T)
+        Implements ILayer3_5_101(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_101(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_101(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_101(Of T)
+        Inherits ILayer2_5_101(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_101(Of T)
+        Inherits ILayer1_5_101(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_101(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_110()
+        GetType(ILayer1_5_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_5_110(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_110_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_110_Inner()
+        Dim w As New TestClass5_110(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_110(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_110(Of T)
+        Implements ILayer3_5_110(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_110(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_110(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_110(Of T)
+        Inherits ILayer2_5_110(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_110(Of T)
+        Inherits ILayer1_5_110(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_110(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+    <Fact>
+    Public Shared Sub Test_Method5_111()
+        GetType(ILayer1_5_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer2_5_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        GetType(ILayer3_5_111(Of Integer)).GetGenericTypeDefinition().GetInterfaces()
+        Test_Method5_111_Inner()
+    End Sub
+
+    <MethodImpl(MethodImplOptions.NoInlining)>
+    Public Shared Sub Test_Method5_111_Inner()
+        Dim w As New TestClass5_111(Of Integer)
+        Dim en As IEnumerator(Of IList(Of Integer)) = DirectCast(w, ILayer1_5_111(Of IList(Of Integer))).GetEnumerator()
+    End Sub
+
+    Public Class TestClass5_111(Of T)
+        Implements ILayer3_5_111(Of T)
+
+        Public ReadOnly Property Count As Integer Implements ILayer2_5_111(Of T).Count
+
+        Public Function GetEnumerator() As IEnumerator(Of IList(Of T)) Implements ILayer1_5_111(Of IList(Of T)).GetEnumerator
+            Return DirectCast(Array.Empty(Of IList(Of T))(), IEnumerable(Of IList(Of T))).GetEnumerator()
+        End Function
+    End Class
+
+    Public Interface ILayer3_5_111(Of T)
+        Inherits ILayer2_5_111(Of T)
+    End Interface
+
+    Public Interface ILayer2_5_111(Of T)
+        Inherits ILayer1_5_111(Of IList(Of T))
+        ReadOnly Property Count As Integer
+    End Interface
+
+    Public Interface ILayer1_5_111(Of T)
+        Function GetEnumerator() As IEnumerator(Of T)
+    End Interface
+
+End Class
diff --git a/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vbproj b/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vbproj
new file mode 100644
index 00000000000000..3a6e3c6c01b1c8
--- /dev/null
+++ b/src/tests/Loader/classloader/regressions/GitHub_124369/GitHub_124369.vbproj
@@ -0,0 +1,6 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <ItemGroup>
+    <Compile Include="GitHub_124369.vb" />
+    <ProjectReference Include="$(TestLibraryProjectPath)" />
+  </ItemGroup>
+</Project>