diff --git a/src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.NetAnalyzers/Microsoft.CodeQuality.Analyzers/Maintainability/MakeTypesInternal.cs b/src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.NetAnalyzers/Microsoft.CodeQuality.Analyzers/Maintainability/MakeTypesInternal.cs
index e405bd81d63e..e8bd0d6f98d3 100644
--- a/src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.NetAnalyzers/Microsoft.CodeQuality.Analyzers/Maintainability/MakeTypesInternal.cs
+++ b/src/Microsoft.CodeAnalysis.NetAnalyzers/src/Microsoft.CodeAnalysis.NetAnalyzers/Microsoft.CodeQuality.Analyzers/Maintainability/MakeTypesInternal.cs
@@ -49,7 +49,7 @@ private void AnalyzeType(SymbolAnalysisContext context)
         {
             INamedTypeSymbol namedTypeSymbol = (INamedTypeSymbol)context.Symbol;
             if (namedTypeSymbol.IsPublic()
-                && GetIdentifier(namedTypeSymbol.DeclaringSyntaxReferences[0].GetSyntax()) is SyntaxToken identifier)
+                && GetIdentifier(namedTypeSymbol.DeclaringSyntaxReferences[0].GetSyntax()) is { SyntaxTree: not null } identifier)
             {
                 context.ReportDiagnostic(identifier.CreateDiagnostic(Rule));
             }
@@ -59,4 +59,4 @@ private void AnalyzeType(SymbolAnalysisContext context)
 
         public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics { get; } = ImmutableArray.Create(Rule);
     }
-}
\ No newline at end of file
+}