diff --git a/src/EditorFeatures/Core/ExternalAccess/VSTypeScript/VSTypeScriptDiagnosticService.cs b/src/EditorFeatures/Core/ExternalAccess/VSTypeScript/VSTypeScriptDiagnosticService.cs
deleted file mode 100644
index 8fb8b95cfd62a..0000000000000
--- a/src/EditorFeatures/Core/ExternalAccess/VSTypeScript/VSTypeScriptDiagnosticService.cs
+++ /dev/null
@@ -1,41 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-
-using System;
-using System.Collections.Immutable;
-using System.Composition;
-using System.Threading;
-using System.Threading.Tasks;
-using Microsoft.CodeAnalysis.ExternalAccess.VSTypeScript.Api;
-using Microsoft.CodeAnalysis.Host.Mef;
-using Roslyn.Utilities;
-
-namespace Microsoft.CodeAnalysis.ExternalAccess.VSTypeScript;
-
-[Export(typeof(IVSTypeScriptDiagnosticService)), Shared]
-[method: ImportingConstructor]
-[method: Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
-internal sealed class VSTypeScriptDiagnosticService() : IVSTypeScriptDiagnosticService
-{
-    public Task<ImmutableArray<VSTypeScriptDiagnosticData>> GetPushDiagnosticsAsync(Workspace workspace, ProjectId projectId, DocumentId documentId, object id, bool includeSuppressedDiagnostics, CancellationToken cancellationToken)
-    {
-        // This type is only for push diagnostics, which is now no longer how any of our diagnostic systems work. So
-        // this just returns nothing.
-        return SpecializedTasks.EmptyImmutableArray<VSTypeScriptDiagnosticData>();
-    }
-
-    [Obsolete]
-    public IDisposable RegisterDiagnosticsUpdatedEventHandler(Action<VSTypeScriptDiagnosticsUpdatedArgsWrapper> action)
-        => new EventHandlerWrapper();
-
-    public IDisposable RegisterDiagnosticsUpdatedEventHandler(Action<ImmutableArray<VSTypeScriptDiagnosticsUpdatedArgsWrapper>> action)
-        => new EventHandlerWrapper();
-
-    private sealed class EventHandlerWrapper : IDisposable
-    {
-        public void Dispose()
-        {
-        }
-    }
-}
diff --git a/src/Features/Core/Portable/ExternalAccess/VSTypeScript/Api/IVSTypeScriptDiagnosticService.cs b/src/Features/Core/Portable/ExternalAccess/VSTypeScript/Api/IVSTypeScriptDiagnosticService.cs
deleted file mode 100644
index 4fd9cf9810021..0000000000000
--- a/src/Features/Core/Portable/ExternalAccess/VSTypeScript/Api/IVSTypeScriptDiagnosticService.cs
+++ /dev/null
@@ -1,20 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-
-using System;
-using System.Collections.Immutable;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace Microsoft.CodeAnalysis.ExternalAccess.VSTypeScript.Api;
-
-internal interface IVSTypeScriptDiagnosticService
-{
-    Task<ImmutableArray<VSTypeScriptDiagnosticData>> GetPushDiagnosticsAsync(Workspace workspace, ProjectId projectId, DocumentId documentId, object id, bool includeSuppressedDiagnostics, CancellationToken cancellationToken);
-
-    [Obsolete]
-    IDisposable RegisterDiagnosticsUpdatedEventHandler(Action<VSTypeScriptDiagnosticsUpdatedArgsWrapper> action);
-
-    IDisposable RegisterDiagnosticsUpdatedEventHandler(Action<ImmutableArray<VSTypeScriptDiagnosticsUpdatedArgsWrapper>> action);
-}