diff --git a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AZC0015Tests.cs b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AZC0015Tests.cs
index b8f821ee9e0..462a30629f1 100644
--- a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AZC0015Tests.cs
+++ b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AZC0015Tests.cs
@@ -44,6 +44,8 @@ await Verifier.CreateAnalyzer(code)
         [InlineData("public Response<int> ClientMethodAsync() { return default; }")]
         [InlineData("public Response<int[]> ClientMethodAsync() { return default; }")]
         [InlineData("public Task<Response<int[]>> ClientMethodAsync() { return default; }")]
+        [InlineData("public NullableResponse<int[]> ClientMethodAsync() { return default; }")]
+        [InlineData("public Task<NullableResponse<int[]>> ClientMethodAsync() { return default; }")]
         [InlineData("public Response ClientMethodAsync() { return default; }")]
         [InlineData("public SomeClient ClientMethod() { return default; }")]
         public async Task AZC0015NotProducedForValidReturnTypes(string usage)
@@ -65,4 +67,4 @@ await Verifier.CreateAnalyzer(code)
                 .RunAsync();
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerTest.cs b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerTest.cs
index dae8708ac76..309336bc00e 100644
--- a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerTest.cs
+++ b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerTest.cs
@@ -16,7 +16,7 @@ namespace Azure.ClientSdk.Analyzers.Tests
     {
         private static readonly ReferenceAssemblies DefaultReferenceAssemblies =
             ReferenceAssemblies.Default.AddPackages(ImmutableArray.Create(
-                new PackageIdentity("Azure.Core", "1.21.0"),
+                new PackageIdentity("Azure.Core", "1.26.0"),
                 new PackageIdentity("Microsoft.Bcl.AsyncInterfaces", "1.1.0"),
                 new PackageIdentity("System.Text.Json", "4.6.0"),
                 new PackageIdentity("Newtonsoft.Json", "12.0.3"),
diff --git a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerVerifier.cs b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerVerifier.cs
index 60a54059dbc..12a8d8e858d 100644
--- a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerVerifier.cs
+++ b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers.Tests/AzureAnalyzerVerifier.cs
@@ -17,7 +17,7 @@ namespace Azure.ClientSdk.Analyzers.Tests
     {
         private static readonly ReferenceAssemblies DefaultReferenceAssemblies =
             ReferenceAssemblies.Default.AddPackages(ImmutableArray.Create(
-                new PackageIdentity("Azure.Core", "1.21.0"),
+                new PackageIdentity("Azure.Core", "1.26.0"),
                 new PackageIdentity("Microsoft.Bcl.AsyncInterfaces", "1.1.0"),
                 new PackageIdentity("System.Text.Json", "4.6.0"),
                 new PackageIdentity("Newtonsoft.Json", "12.0.3"),
diff --git a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers/ClientMethodsAnalyzer.cs b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers/ClientMethodsAnalyzer.cs
index c24ff2ebf7c..ab20919b072 100644
--- a/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers/ClientMethodsAnalyzer.cs
+++ b/src/dotnet/Azure.ClientSdk.Analyzers/Azure.ClientSdk.Analyzers/ClientMethodsAnalyzer.cs
@@ -27,7 +27,7 @@ static bool SupportsCancellationsParameter(IParameterSymbol parameterSymbol)
             {
                 return (parameterSymbol.Name == "cancellationToken" && parameterSymbol.Type.Name == "CancellationToken") ||
                        (parameterSymbol.Name == "context" && parameterSymbol.Type.Name == "RequestContext");
-            }
+            }
 
             CheckClientMethodReturnType(context, member);
 
@@ -100,6 +100,7 @@ bool IsOrImplements(ITypeSymbol typeSymbol, string typeName)
             }
 
             if (IsOrImplements(unwrappedType, "Response") ||
+                IsOrImplements(unwrappedType, "NullableResponse") ||
                 IsOrImplements(unwrappedType, "Operation") ||
                 IsOrImplements(originalType, "Pageable") ||
                 IsOrImplements(originalType, "AsyncPageable") ||