diff --git a/Connectors/ArcGIS/Speckle.Connectors.ArcGIS3/Operations/Send/ArcGISRootObjectBuilder.cs b/Connectors/ArcGIS/Speckle.Connectors.ArcGIS3/Operations/Send/ArcGISRootObjectBuilder.cs
index b7b00916b..643333b0a 100644
--- a/Connectors/ArcGIS/Speckle.Connectors.ArcGIS3/Operations/Send/ArcGISRootObjectBuilder.cs
+++ b/Connectors/ArcGIS/Speckle.Connectors.ArcGIS3/Operations/Send/ArcGISRootObjectBuilder.cs
@@ -98,7 +98,7 @@ public class ArcGISRootObjectBuilder : IRootObjectBuilder<MapMember>
         // don't use cache for group layers
         if (
           mapMember is not GroupLayer
-          && _sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference value)
+          && _sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference? value)
         )
         {
           converted = value;
diff --git a/Connectors/Autocad/Speckle.Connectors.AutocadShared/Operations/Send/AutocadRootObjectBuilder.cs b/Connectors/Autocad/Speckle.Connectors.AutocadShared/Operations/Send/AutocadRootObjectBuilder.cs
index 78724301b..e0624513e 100644
--- a/Connectors/Autocad/Speckle.Connectors.AutocadShared/Operations/Send/AutocadRootObjectBuilder.cs
+++ b/Connectors/Autocad/Speckle.Connectors.AutocadShared/Operations/Send/AutocadRootObjectBuilder.cs
@@ -108,7 +108,7 @@ public class AutocadRootObjectBuilder : IRootObjectBuilder<AutocadRootObject>
           {
             converted = instanceProxy;
           }
-          else if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference value))
+          else if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference? value))
           {
             converted = value;
             cacheHitCount++;
diff --git a/Connectors/Revit/Speckle.Connectors.RevitShared/Operations/Send/RevitRootObjectBuilder.cs b/Connectors/Revit/Speckle.Connectors.RevitShared/Operations/Send/RevitRootObjectBuilder.cs
index 10bcfef88..b3b293e8c 100644
--- a/Connectors/Revit/Speckle.Connectors.RevitShared/Operations/Send/RevitRootObjectBuilder.cs
+++ b/Connectors/Revit/Speckle.Connectors.RevitShared/Operations/Send/RevitRootObjectBuilder.cs
@@ -99,7 +99,7 @@ public class RevitRootObjectBuilder : IRootObjectBuilder<ElementId>
         try
         {
           Base converted;
-          if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference value))
+          if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference? value))
           {
             converted = value;
             cacheHitCount++;
diff --git a/Connectors/Rhino/Speckle.Connectors.RhinoShared/Operations/Send/RhinoRootObjectBuilder.cs b/Connectors/Rhino/Speckle.Connectors.RhinoShared/Operations/Send/RhinoRootObjectBuilder.cs
index 7b6d61c7f..278cc4eb0 100644
--- a/Connectors/Rhino/Speckle.Connectors.RhinoShared/Operations/Send/RhinoRootObjectBuilder.cs
+++ b/Connectors/Rhino/Speckle.Connectors.RhinoShared/Operations/Send/RhinoRootObjectBuilder.cs
@@ -146,7 +146,7 @@ public class RhinoRootObjectBuilder : IRootObjectBuilder<RhinoObject>
       {
         converted = instanceProxies[applicationId];
       }
-      else if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference value))
+      else if (_sendConversionCache.TryGetValue(sendInfo.ProjectId, applicationId, out ObjectReference? value))
       {
         converted = value;
       }
diff --git a/Sdk/Speckle.Connectors.Utils/Caching/ISendConversionCache.cs b/Sdk/Speckle.Connectors.Utils/Caching/ISendConversionCache.cs
index 02c11e65c..bff42e3e8 100644
--- a/Sdk/Speckle.Connectors.Utils/Caching/ISendConversionCache.cs
+++ b/Sdk/Speckle.Connectors.Utils/Caching/ISendConversionCache.cs
@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using Speckle.Sdk.Models;
 
 namespace Speckle.Connectors.Utils.Caching;
@@ -20,5 +21,5 @@ public interface ISendConversionCache
   /// <param name="objectIds"></param>
   public void EvictObjects(IEnumerable<string> objectIds);
   public void ClearCache();
-  bool TryGetValue(string projectId, string applicationId, out ObjectReference objectReference);
+  bool TryGetValue(string projectId, string applicationId, [NotNullWhen(true)] out ObjectReference? objectReference);
 }
diff --git a/Sdk/Speckle.Connectors.Utils/Caching/NullSendConversionCache.cs b/Sdk/Speckle.Connectors.Utils/Caching/NullSendConversionCache.cs
index 3ba7e8f14..65a5149b1 100644
--- a/Sdk/Speckle.Connectors.Utils/Caching/NullSendConversionCache.cs
+++ b/Sdk/Speckle.Connectors.Utils/Caching/NullSendConversionCache.cs
@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using Speckle.Sdk.Models;
 
 namespace Speckle.Connectors.Utils.Caching;
@@ -13,9 +14,13 @@ public class NullSendConversionCache : ISendConversionCache
 
   public void ClearCache() { }
 
-  public bool TryGetValue(string projectId, string applicationId, out ObjectReference objectReference)
+  public bool TryGetValue(
+    string projectId,
+    string applicationId,
+    [NotNullWhen(true)] out ObjectReference? objectReference
+  )
   {
-    objectReference = new ObjectReference();
+    objectReference = null;
     return false;
   }
 }
diff --git a/Sdk/Speckle.Connectors.Utils/Caching/SendConversionCache.cs b/Sdk/Speckle.Connectors.Utils/Caching/SendConversionCache.cs
index 4fe7d62bd..7d9b8ece0 100644
--- a/Sdk/Speckle.Connectors.Utils/Caching/SendConversionCache.cs
+++ b/Sdk/Speckle.Connectors.Utils/Caching/SendConversionCache.cs
@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using Speckle.Sdk.Models;
 
 namespace Speckle.Connectors.Utils.Caching;
@@ -25,6 +26,9 @@ public class SendConversionCache : ISendConversionCache
 
   public void ClearCache() => Cache.Clear();
 
-  public bool TryGetValue(string projectId, string applicationId, out ObjectReference objectReference) =>
-    Cache.TryGetValue((applicationId, projectId), out objectReference);
+  public bool TryGetValue(
+    string projectId,
+    string applicationId,
+    [NotNullWhen(true)] out ObjectReference? objectReference
+  ) => Cache.TryGetValue((applicationId, projectId), out objectReference);
 }