diff --git a/src/Identity/Core/src/BuilderExtensions.cs b/src/Identity/Core/src/BuilderExtensions.cs
deleted file mode 100644
index e1f9defb43..0000000000
--- a/src/Identity/Core/src/BuilderExtensions.cs
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Identity extensions for <see cref="IApplicationBuilder"/>.
-    /// </summary>
-    public static class BuilderExtensions
-    {
-        /// <summary>
-        /// <para>
-        /// This method is obsolete and will be removed in a future version.
-        /// The recommended alternative is <see cref="AuthAppBuilderExtensions.UseAuthentication(IApplicationBuilder)" />
-        /// </para>
-        /// <para>
-        /// Enables ASP.NET identity for the current application.
-        /// </para>
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> instance this method extends.</param>
-        /// <returns>The <see cref="IApplicationBuilder"/> instance this method extends.</returns>
-        [Obsolete(
-            "This method is obsolete and will be removed in a future version. " +
-            "The recommended alternative is UseAuthentication(). " +
-            "See https://go.microsoft.com/fwlink/?linkid=845470")]
-        public static IApplicationBuilder UseIdentity(this IApplicationBuilder app)
-            => app.UseAuthentication();
-    }
-}
diff --git a/src/Security/Authentication/Cookies/src/CookieAppBuilderExtensions.cs b/src/Security/Authentication/Cookies/src/CookieAppBuilderExtensions.cs
deleted file mode 100644
index bdfd43c796..0000000000
--- a/src/Security/Authentication/Cookies/src/CookieAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.Cookies;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add cookie authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class CookieAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseCookieAuthentication is obsolete. Configure Cookie authentication with AddAuthentication().AddCookie in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseCookieAuthentication is obsolete. Configure Cookie authentication with AddAuthentication().AddCookie in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseCookieAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseCookieAuthentication is obsolete. Configure Cookie authentication with AddAuthentication().AddCookie in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="CookieAuthenticationOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseCookieAuthentication is obsolete. Configure Cookie authentication with AddAuthentication().AddCookie in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseCookieAuthentication(this IApplicationBuilder app, CookieAuthenticationOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/Facebook/src/FacebookAppBuilderExtensions.cs b/src/Security/Authentication/Facebook/src/FacebookAppBuilderExtensions.cs
deleted file mode 100644
index a94dc7bc45..0000000000
--- a/src/Security/Authentication/Facebook/src/FacebookAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.Facebook;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add Facebook authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class FacebookAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseFacebookAuthentication is obsolete. Configure Facebook authentication with AddAuthentication().AddFacebook in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseFacebookAuthentication is obsolete. Configure Facebook authentication with AddAuthentication().AddFacebook in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseFacebookAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseFacebookAuthentication is obsolete. Configure Facebook authentication with AddAuthentication().AddFacebook in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="FacebookOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseFacebookAuthentication is obsolete. Configure Facebook authentication with AddAuthentication().AddFacebook in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseFacebookAuthentication(this IApplicationBuilder app, FacebookOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/Google/src/GoogleAppBuilderExtensions.cs b/src/Security/Authentication/Google/src/GoogleAppBuilderExtensions.cs
deleted file mode 100644
index 4302d20db1..0000000000
--- a/src/Security/Authentication/Google/src/GoogleAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.Google;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add Google authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class GoogleAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseGoogleAuthentication is obsolete. Configure Google authentication with AddAuthentication().AddGoogle in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseGoogleAuthentication is obsolete. Configure Google authentication with AddAuthentication().AddGoogle in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseGoogleAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseGoogleAuthentication is obsolete. Configure Google authentication with AddAuthentication().AddGoogle in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="GoogleOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseGoogleAuthentication is obsolete. Configure Google authentication with AddAuthentication().AddGoogle in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseGoogleAuthentication(this IApplicationBuilder app, GoogleOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
diff --git a/src/Security/Authentication/JwtBearer/src/JwtBearerAppBuilderExtensions.cs b/src/Security/Authentication/JwtBearer/src/JwtBearerAppBuilderExtensions.cs
deleted file mode 100644
index 0cfc97573c..0000000000
--- a/src/Security/Authentication/JwtBearer/src/JwtBearerAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.JwtBearer;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add OpenIdConnect Bearer authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class JwtBearerAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseJwtBearerAuthentication is obsolete. Configure JwtBearer authentication with AddAuthentication().AddJwtBearer in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseJwtBearerAuthentication is obsolete. Configure JwtBearer authentication with AddAuthentication().AddJwtBearer in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseJwtBearerAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseJwtBearerAuthentication is obsolete. Configure JwtBearer authentication with AddAuthentication().AddJwtBearer in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A  <see cref="JwtBearerOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseJwtBearerAuthentication is obsolete. Configure JwtBearer authentication with AddAuthentication().AddJwtBearer in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseJwtBearerAuthentication(this IApplicationBuilder app, JwtBearerOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/MicrosoftAccount/src/MicrosoftAccountAppBuilderExtensions.cs b/src/Security/Authentication/MicrosoftAccount/src/MicrosoftAccountAppBuilderExtensions.cs
deleted file mode 100644
index 7fd71d7a9b..0000000000
--- a/src/Security/Authentication/MicrosoftAccount/src/MicrosoftAccountAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.MicrosoftAccount;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add Microsoft Account authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class MicrosoftAccountAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseMicrosoftAccountAuthentication is obsolete. Configure MicrosoftAccount authentication with AddAuthentication().AddMicrosoftAccount in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseMicrosoftAccountAuthentication is obsolete. Configure MicrosoftAccount authentication with AddAuthentication().AddMicrosoftAccount in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseMicrosoftAccountAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseMicrosoftAccountAuthentication is obsolete. Configure MicrosoftAccount authentication with AddAuthentication().AddMicrosoftAccount in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="MicrosoftAccountOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseMicrosoftAccountAuthentication is obsolete. Configure MicrosoftAccount authentication with AddAuthentication().AddMicrosoftAccount in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseMicrosoftAccountAuthentication(this IApplicationBuilder app, MicrosoftAccountOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/OAuth/src/OAuthAppBuilderExtensions.cs b/src/Security/Authentication/OAuth/src/OAuthAppBuilderExtensions.cs
deleted file mode 100644
index d55f311f7b..0000000000
--- a/src/Security/Authentication/OAuth/src/OAuthAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.OAuth;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add OAuth 2.0 authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class OAuthAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseOAuthAuthentication is obsolete. Configure OAuth authentication with AddAuthentication().AddOAuth in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseOAuthAuthentication is obsolete. Configure OAuth authentication with AddAuthentication().AddOAuth in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseOAuthAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseOAuthAuthentication is obsolete. Configure OAuth authentication with AddAuthentication().AddOAuth in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="OAuthOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseOAuthAuthentication is obsolete. Configure OAuth authentication with AddAuthentication().AddOAuth in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseOAuthAuthentication(this IApplicationBuilder app, OAuthOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/OpenIdConnect/src/OpenIdConnectAppBuilderExtensions.cs b/src/Security/Authentication/OpenIdConnect/src/OpenIdConnectAppBuilderExtensions.cs
deleted file mode 100644
index 0746ae3fdb..0000000000
--- a/src/Security/Authentication/OpenIdConnect/src/OpenIdConnectAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.OpenIdConnect;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add OpenID Connect authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class OpenIdConnectAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseOpenIdConnectAuthentication is obsolete. Configure OpenIdConnect authentication with AddAuthentication().AddOpenIdConnect in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseOpenIdConnectAuthentication is obsolete. Configure OpenIdConnect authentication with AddAuthentication().AddOpenIdConnect in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseOpenIdConnectAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseOpenIdConnectAuthentication is obsolete. Configure OpenIdConnect authentication with AddAuthentication().AddOpenIdConnect in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">A <see cref="OpenIdConnectOptions"/> that specifies options for the handler.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseOpenIdConnectAuthentication is obsolete. Configure OpenIdConnect authentication with AddAuthentication().AddOpenIdConnect in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseOpenIdConnectAuthentication(this IApplicationBuilder app, OpenIdConnectOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/Security/Authentication/Twitter/src/TwitterAppBuilderExtensions.cs b/src/Security/Authentication/Twitter/src/TwitterAppBuilderExtensions.cs
deleted file mode 100644
index 36e1111da6..0000000000
--- a/src/Security/Authentication/Twitter/src/TwitterAppBuilderExtensions.cs
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using Microsoft.AspNetCore.Authentication.Twitter;
-
-namespace Microsoft.AspNetCore.Builder
-{
-    /// <summary>
-    /// Extension methods to add Twitter authentication capabilities to an HTTP application pipeline.
-    /// </summary>
-    public static class TwitterAppBuilderExtensions
-    {
-        /// <summary>
-        /// UseTwitterAuthentication is obsolete. Configure Twitter authentication with AddAuthentication().AddTwitter in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseTwitterAuthentication is obsolete. Configure Twitter authentication with AddAuthentication().AddTwitter in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseTwitterAuthentication(this IApplicationBuilder app)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-
-        /// <summary>
-        /// UseTwitterAuthentication is obsolete. Configure Twitter authentication with AddAuthentication().AddTwitter in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.
-        /// </summary>
-        /// <param name="app">The <see cref="IApplicationBuilder"/> to add the handler to.</param>
-        /// <param name="options">An action delegate to configure the provided <see cref="TwitterOptions"/>.</param>
-        /// <returns>A reference to this instance after the operation has completed.</returns>
-        [Obsolete("UseTwitterAuthentication is obsolete. Configure Twitter authentication with AddAuthentication().AddTwitter in ConfigureServices. See https://go.microsoft.com/fwlink/?linkid=845470 for more details.", error: true)]
-        public static IApplicationBuilder UseTwitterAuthentication(this IApplicationBuilder app, TwitterOptions options)
-        {
-            throw new NotSupportedException("This method is no longer supported, see https://go.microsoft.com/fwlink/?linkid=845470");
-        }
-    }
-}
\ No newline at end of file