diff --git a/sdk/dotNet/README.md b/sdk/dotNet/README.md
index c0617be6..9deb1b5c 100644
--- a/sdk/dotNet/README.md
+++ b/sdk/dotNet/README.md
@@ -5,6 +5,7 @@
 
 ## 16.6.6
 
+* KSM-490 - Switch some internal classes to public - for use in plugins
 * KSM-515 - Update to Bouncy Castle 2.4.0
 
 ## 16.6.5
diff --git a/sdk/dotNet/SecretsManager/Notation.cs b/sdk/dotNet/SecretsManager/Notation.cs
index 5dd84098..07f1b98f 100644
--- a/sdk/dotNet/SecretsManager/Notation.cs
+++ b/sdk/dotNet/SecretsManager/Notation.cs
@@ -108,7 +108,7 @@ KeeperRecordField FindField(string fieldName)
         }
 
         // data class to represent parsed notation section
-        internal class NotationSection
+        public class NotationSection
         {
             public string Section = null;   // section name - ex. prefix
             public bool IsPresent = false;  // presence flag
@@ -281,7 +281,7 @@ private static NotationSection ParseSection(string notation, string section, int
             return result;
         }
 
-        internal static List<NotationSection> ParseNotation(string notation, bool legacyMode = false)
+        public static List<NotationSection> ParseNotation(string notation, bool legacyMode = false)
         {
             if (string.IsNullOrEmpty(notation))
                 throw new Exception("Keeper notation is missing or invalid.");
diff --git a/sdk/dotNet/SecretsManager/SecretsManagerClient.cs b/sdk/dotNet/SecretsManager/SecretsManagerClient.cs
index 44202c7a..bcb6eec6 100644
--- a/sdk/dotNet/SecretsManager/SecretsManagerClient.cs
+++ b/sdk/dotNet/SecretsManager/SecretsManagerClient.cs
@@ -5,14 +5,11 @@
 using System.Linq;
 using System.Net;
 using System.Reflection;
-using System.Runtime.CompilerServices;
 using System.Text;
 using System.Text.Json;
 using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 
-[assembly: InternalsVisibleTo("SecretsManager.Test.Core")]
-
 namespace SecretsManager
 {
     using GetRandomBytesFunction = Func<int, byte[]>;
@@ -1412,7 +1409,7 @@ private static TransmissionKey GenerateTransmissionKey(IKeyValueStorage storage)
 
         [SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
         [SuppressMessage("ReSharper", "UnusedAutoPropertyAccessor.Global")]
-        internal static GetRandomBytesFunction TransmissionKeyStub { get; set; }
+        public static GetRandomBytesFunction TransmissionKeyStub { get; set; }
 
         private static EncryptedPayload EncryptAndSignPayload<T>(IKeyValueStorage storage,
             TransmissionKey transmissionKey, T payload)