diff --git a/src/Tools/BuildBoss/InternalsVisibleTo.cs b/src/Tools/BuildBoss/InternalsVisibleTo.cs
index 74852c2c79b644c9908ca70f1cbdf4c30cfc7514..455624476af3ec2b267baf990696839f3b43a90a 100644
--- a/src/Tools/BuildBoss/InternalsVisibleTo.cs
+++ b/src/Tools/BuildBoss/InternalsVisibleTo.cs
@@ -21,13 +21,24 @@ public override string ToString()
         {
             var element = new XElement("InternalsVisibleTo");
             if (TargetAssembly is object)
+            {
                 element.Add(new XAttribute("Include", TargetAssembly));
+            }
+
             if (PublicKey is object)
+            {
                 element.Add(new XAttribute("Key", PublicKey));
+            }
+
             if (LoadsWithinVisualStudio is object)
+            {
                 element.Add(new XAttribute("LoadsWithinVisualStudio", LoadsWithinVisualStudio));
+            }
+
             if (WorkItem is object)
+            {
                 element.Add(new XAttribute("WorkItem", WorkItem));
+            }
 
             return element.ToString();
         }
diff --git a/src/Tools/BuildBoss/ProjectCheckerUtil.cs b/src/Tools/BuildBoss/ProjectCheckerUtil.cs
index 486ad9eb35e5a504c6dc769cdf70295fa8986448..b1e3b95e47c342361a1c399e3fd51a51845e6f3b 100644
--- a/src/Tools/BuildBoss/ProjectCheckerUtil.cs
+++ b/src/Tools/BuildBoss/ProjectCheckerUtil.cs
@@ -255,8 +255,14 @@ private bool CheckInternalsVisibleTo(TextWriter textWriter)
                     continue;
                 }
 
-                if (Uri.TryCreate(internalsVisibleTo.WorkItem, UriKind.Absolute, out _))
+                if (!string.IsNullOrEmpty(internalsVisibleTo.WorkItem))
                 {
+                    if (!Uri.TryCreate(internalsVisibleTo.WorkItem, UriKind.Absolute, out _))
+                    {
+                        textWriter.WriteLine($"InternalsVisibleTo for external assembly '{internalsVisibleTo.TargetAssembly}' does not have a valid URI specified for {nameof(InternalsVisibleTo.WorkItem)}.");
+                        allGood = false;
+                    }
+
                     // A work item is tracking elimination of this IVT
                     continue;
                 }