diff --git a/src/Servers/HttpSys/test/FunctionalTests/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests.csproj b/src/Servers/HttpSys/test/FunctionalTests/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests.csproj
index 27d3add58dd3..08276e6a23fd 100644
--- a/src/Servers/HttpSys/test/FunctionalTests/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests.csproj
+++ b/src/Servers/HttpSys/test/FunctionalTests/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests.csproj
@@ -13,7 +13,7 @@
   <ItemGroup>
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/IIS/IIS/test/IIS.FunctionalTests/IIS.FunctionalTests.csproj b/src/Servers/IIS/IIS/test/IIS.FunctionalTests/IIS.FunctionalTests.csproj
index 159eb0359e21..8ed1c6634ec8 100644
--- a/src/Servers/IIS/IIS/test/IIS.FunctionalTests/IIS.FunctionalTests.csproj
+++ b/src/Servers/IIS/IIS/test/IIS.FunctionalTests/IIS.FunctionalTests.csproj
@@ -29,7 +29,7 @@
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" Exclude="$(SharedSourceRoot)ServerInfrastructure\DuplexPipe.cs" />
     <Compile Include="$(SharedSourceRoot)ValueTaskExtensions\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/IIS/IIS/test/IIS.LongTests/IIS.LongTests.csproj b/src/Servers/IIS/IIS/test/IIS.LongTests/IIS.LongTests.csproj
index 5ab3cdd0b60b..a81c3fec2029 100644
--- a/src/Servers/IIS/IIS/test/IIS.LongTests/IIS.LongTests.csproj
+++ b/src/Servers/IIS/IIS/test/IIS.LongTests/IIS.LongTests.csproj
@@ -25,7 +25,7 @@
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" Exclude="$(SharedSourceRoot)ServerInfrastructure\DuplexPipe.cs" />
     <Compile Include="$(SharedSourceRoot)ValueTaskExtensions\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/IIS/IIS/test/IIS.NewHandler.FunctionalTests/IIS.NewHandler.FunctionalTests.csproj b/src/Servers/IIS/IIS/test/IIS.NewHandler.FunctionalTests/IIS.NewHandler.FunctionalTests.csproj
index ecca2b77471c..e38af72c179b 100644
--- a/src/Servers/IIS/IIS/test/IIS.NewHandler.FunctionalTests/IIS.NewHandler.FunctionalTests.csproj
+++ b/src/Servers/IIS/IIS/test/IIS.NewHandler.FunctionalTests/IIS.NewHandler.FunctionalTests.csproj
@@ -18,7 +18,7 @@
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" Exclude="$(SharedSourceRoot)ServerInfrastructure\DuplexPipe.cs" />
     <Compile Include="$(SharedSourceRoot)ValueTaskExtensions\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/IIS/IIS/test/IIS.NewShim.FunctionalTests/IIS.NewShim.FunctionalTests.csproj b/src/Servers/IIS/IIS/test/IIS.NewShim.FunctionalTests/IIS.NewShim.FunctionalTests.csproj
index cf87933172da..40e30287b319 100644
--- a/src/Servers/IIS/IIS/test/IIS.NewShim.FunctionalTests/IIS.NewShim.FunctionalTests.csproj
+++ b/src/Servers/IIS/IIS/test/IIS.NewShim.FunctionalTests/IIS.NewShim.FunctionalTests.csproj
@@ -28,7 +28,7 @@
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" Exclude="$(SharedSourceRoot)ServerInfrastructure\DuplexPipe.cs" />
     <Compile Include="$(SharedSourceRoot)ValueTaskExtensions\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/IIS/IIS/test/IISExpress.FunctionalTests/IISExpress.FunctionalTests.csproj b/src/Servers/IIS/IIS/test/IISExpress.FunctionalTests/IISExpress.FunctionalTests.csproj
index 91a683979153..15ad8db11a2f 100644
--- a/src/Servers/IIS/IIS/test/IISExpress.FunctionalTests/IISExpress.FunctionalTests.csproj
+++ b/src/Servers/IIS/IIS/test/IISExpress.FunctionalTests/IISExpress.FunctionalTests.csproj
@@ -30,7 +30,7 @@
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2\" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" Exclude="$(SharedSourceRoot)ServerInfrastructure\DuplexPipe.cs" />
     <Compile Include="$(SharedSourceRoot)ValueTaskExtensions\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Servers/Kestrel/samples/http2cat/http2cat.csproj b/src/Servers/Kestrel/samples/http2cat/http2cat.csproj
index 2b7b045beebd..ba9b19a9e2e2 100644
--- a/src/Servers/Kestrel/samples/http2cat/http2cat.csproj
+++ b/src/Servers/Kestrel/samples/http2cat/http2cat.csproj
@@ -9,7 +9,7 @@
   <ItemGroup>
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" LinkBase="Shared\Http2" />
     <Compile Include="$(SharedSourceRoot)runtime\IHttpStreamHeadersHandler.cs" LinkBase="Shared\IHttpStreamHeadersHandler.cs" />
-    <Compile Include="$(SharedSourceRoot)runtime\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
+    <Compile Include="$(SharedSourceRoot)Hpack\Obsoletions.cs" LinkBase="Shared\Obsoletions.cs" />
     <Compile Include="$(SharedSourceRoot)runtime\SR.cs" LinkBase="Shared\SR.cs" />
     <Compile Include="$(SharedSourceRoot)Http2cat\**\*.cs" LinkBase="Shared\Http2cat" />
     <Compile Include="$(SharedSourceRoot)ServerInfrastructure\**\*.cs" LinkBase="Shared\" />
diff --git a/src/Shared/Hpack/Obsoletions.cs b/src/Shared/Hpack/Obsoletions.cs
new file mode 100644
index 000000000000..6543bcabbb2c
--- /dev/null
+++ b/src/Shared/Hpack/Obsoletions.cs
@@ -0,0 +1,13 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System;
+
+// Copied from runtime, referenced by shared code.
+internal static class Obsoletions
+{
+    internal const string SharedUrlFormat = "https://aka.ms/dotnet-warnings/{0}";
+
+    internal const string LegacyFormatterImplMessage = "This API supports obsolete formatter-based serialization. It should not be called or extended by application code.";
+    internal const string LegacyFormatterImplDiagId = "SYSLIB0051";
+}
diff --git a/src/Shared/runtime/Obsoletions.cs b/src/Shared/runtime/Obsoletions.cs
deleted file mode 100644
index d51213ccd6e3..000000000000
--- a/src/Shared/runtime/Obsoletions.cs
+++ /dev/null
@@ -1,13 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-
-namespace System
-{
-    internal static class Obsoletions
-    {
-        internal const string SharedUrlFormat = "https://aka.ms/dotnet-warnings/{0}";
-
-        internal const string LegacyFormatterImplMessage = "This API supports obsolete formatter-based serialization. It should not be called or extended by application code.";
-        internal const string LegacyFormatterImplDiagId = "SYSLIB0051";
-    }
-}
diff --git a/src/Shared/test/Shared.Tests/Microsoft.AspNetCore.Shared.Tests.csproj b/src/Shared/test/Shared.Tests/Microsoft.AspNetCore.Shared.Tests.csproj
index 678f8f81516e..21babaf54745 100644
--- a/src/Shared/test/Shared.Tests/Microsoft.AspNetCore.Shared.Tests.csproj
+++ b/src/Shared/test/Shared.Tests/Microsoft.AspNetCore.Shared.Tests.csproj
@@ -16,6 +16,7 @@
     <Compile Include="$(SharedSourceRoot)runtime\*.cs" Link="Shared\runtime\%(Filename)%(Extension)" />
     <Compile Include="$(SharedSourceRoot)runtime\Http2\**\*.cs" Link="Shared\runtime\Http2\%(Filename)%(Extension)" />
     <Compile Include="$(SharedSourceRoot)runtime\Http3\**\*.cs" Link="Shared\runtime\Http3\%(Filename)%(Extension)" />
+    <Compile Include="$(SharedSourceRoot)Hpack\*.cs" Link="Shared\Hpack\%(Filename)%(Extension)" />
     <Compile Include="$(SharedSourceRoot)HttpSys\**\*.cs" Link="Shared\HttpSys\%(Filename)%(Extension)" />
     <Compile Include="$(SharedSourceRoot)NonCapturingTimer\*.cs" Link="Shared\NonCapturingTimer\%(Filename)%(Extension)" />
     <Compile Include="$(SharedSourceRoot)ObjectMethodExecutor\*.cs" Link="Shared\ObjectMethodExecutor\%(Filename)%(Extension)" />