diff --git a/src/Testing/Directory.Build.props b/src/Testing/Directory.Build.props
new file mode 100644
index 0000000000..68f87d4f24
--- /dev/null
+++ b/src/Testing/Directory.Build.props
@@ -0,0 +1,8 @@
+<Project>
+  <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory)..\, Directory.Build.props))\Directory.Build.props" />
+
+  <PropertyGroup>
+    <!-- These projects depend on a 3rd party source -->
+    <ExcludeFromSourceBuild>true</ExcludeFromSourceBuild>
+  </PropertyGroup>
+</Project>