diff --git a/src/CodeGenHelpers/DocumentationComment.cs b/src/CodeGenHelpers/DocumentationComment.cs
index 5021b19..3e5ac54 100644
--- a/src/CodeGenHelpers/DocumentationComment.cs
+++ b/src/CodeGenHelpers/DocumentationComment.cs
@@ -13,13 +13,13 @@ internal DocumentationComment(bool supportsParameterDoc = false)
                 : null;
         }
 
-        internal string? Summary { get; set; }
+        internal string Summary { get; set; }
 
-        internal Dictionary<string, string>? ParameterDoc { get; }
+        internal Dictionary<string, string> ParameterDoc { get; }
 
         internal bool InheritDoc { get; set; }
 
-        internal string? InheritFrom { get; set; }
+        internal string InheritFrom { get; set; }
 
         internal void Write(ref CodeWriter writer)
         {