diff --git a/src/Storm.AzureFrontDoorFilter/AzureFrontDoorFilterMiddleware.cs b/src/Storm.AzureFrontDoorFilter/AzureFrontDoorFilterMiddleware.cs
index f1ce517..28ea618 100644
--- a/src/Storm.AzureFrontDoorFilter/AzureFrontDoorFilterMiddleware.cs
+++ b/src/Storm.AzureFrontDoorFilter/AzureFrontDoorFilterMiddleware.cs
@@ -60,8 +60,13 @@ public async Task InvokeAsync(HttpContext context)
             }
         }
 
-        private static string GetHeaderValueOrDefault(IHeaderDictionary headers, string headerName, string defaultValue = default)
+        private static string? GetHeaderValueOrDefault(IHeaderDictionary headers, string headerName, string? defaultValue = default)
         {
+            if (headerName is null)
+            {
+                throw new ArgumentNullException(nameof(headerName));
+            }
+
             if (headers.TryGetValue(headerName, out var headerValue))
             {
                 return headerValue;
@@ -77,8 +82,8 @@ private bool IsAzureFrontDoorRequest(HttpRequest request)
                 return true;
             }
 
-            var afdId = GetHeaderValueOrDefault(request.Headers, AfdIdHeaderName);
-            return approvedAfdIds.Contains(afdId);
+            var afdId = GetHeaderValueOrDefault(request.Headers, AfdIdHeaderName, AllowAllValue);
+            return approvedAfdIds.Contains(afdId ?? AllowAllValue);
         }
     }
 }
diff --git a/src/Storm.AzureFrontDoorFilter/Storm.AzureFrontDoorFilter.csproj b/src/Storm.AzureFrontDoorFilter/Storm.AzureFrontDoorFilter.csproj
index ad4094b..2439645 100644
--- a/src/Storm.AzureFrontDoorFilter/Storm.AzureFrontDoorFilter.csproj
+++ b/src/Storm.AzureFrontDoorFilter/Storm.AzureFrontDoorFilter.csproj
@@ -3,6 +3,13 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <LangVersion>8</LangVersion>
+    <GeneratePackageOnBuild>false</GeneratePackageOnBuild>
+    <Authors>Phil Oyston, StormID</Authors>
+    <Company>Storm ID</Company>
+    <Description>Provides middleware to filter access to your web application based on the request originating through a specified set of Azure Front Door resources.</Description>
+    <PackageTags>azure front-door dotnet</PackageTags>
+    <PackageLicenseFile>LICENSE</PackageLicenseFile>
+    <PackageProjectUrl>https://github.com/stormid/storm-azurefrontdoorfilter</PackageProjectUrl>
   </PropertyGroup>
 
   <ItemGroup>
@@ -12,4 +19,11 @@
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="3.1.8" />
   </ItemGroup>
 
+  <ItemGroup>
+    <None Include="..\..\LICENSE">
+      <Pack>True</Pack>
+      <PackagePath></PackagePath>
+    </None>
+  </ItemGroup>
+
 </Project>