diff --git a/GVFS/GVFS.UnitTests/Virtualization/FileSystemCallbacksTests.cs b/GVFS/GVFS.UnitTests/Virtualization/FileSystemCallbacksTests.cs
index 3a515c3b5..7ab7b13de 100644
--- a/GVFS/GVFS.UnitTests/Virtualization/FileSystemCallbacksTests.cs
+++ b/GVFS/GVFS.UnitTests/Virtualization/FileSystemCallbacksTests.cs
@@ -119,6 +119,7 @@ public void GetMetadataForHeartBeatDoesNotChangeEventLevelWhenNoPlaceholderHaveB
                 metadata.ShouldContain("ModifiedPathsCount", 1);
                 metadata.ShouldContain("FilePlaceholderCount", 0);
                 metadata.ShouldContain(nameof(RepoMetadata.Instance.EnlistmentId), RepoMetadata.Instance.EnlistmentId);
+                metadata.ShouldContain("IsSendingAnonymousRequests", true);
             }
 
             mockPlaceholderDb.VerifyAll();
@@ -159,7 +160,7 @@ public void GetMetadataForHeartBeatDoesSetsEventLevelToInformationalWhenPlacehol
                 eventLevel.ShouldEqual(EventLevel.Informational);
 
                 // "ModifiedPathsCount" should be 1 because ".gitattributes" is always present
-                metadata.Count.ShouldEqual(8);
+                metadata.Count.ShouldEqual(9);
                 metadata.ContainsKey("FilePlaceholderCreation").ShouldBeTrue();
                 metadata.TryGetValue("FilePlaceholderCreation", out object fileNestedMetadata);
                 GVFSJsonOptions.Serialize(fileNestedMetadata).ShouldContain("\"ProcessName1\":\"GVFS.UnitTests.exe\"");
@@ -169,6 +170,7 @@ public void GetMetadataForHeartBeatDoesSetsEventLevelToInformationalWhenPlacehol
                 metadata.ShouldContain("FolderPlaceholderCount", 0);
                 metadata.ShouldContain(nameof(RepoMetadata.Instance.EnlistmentId), RepoMetadata.Instance.EnlistmentId);
                 metadata.ContainsKey("PhysicalDiskInfo").ShouldBeTrue();
+                metadata.ShouldContain("IsSendingAnonymousRequests", true);
 
                 // Create more placeholders
                 fileSystemCallbacks.OnPlaceholderFileCreated("test.txt", "2222233333444445555566666777778888899999", "GVFS.UnitTests.exe2");
@@ -182,7 +184,7 @@ public void GetMetadataForHeartBeatDoesSetsEventLevelToInformationalWhenPlacehol
                 eventLevel = writeToLogFile2 ? EventLevel.Informational : EventLevel.Verbose;
                 eventLevel.ShouldEqual(EventLevel.Informational);
 
-                metadata.Count.ShouldEqual(8);
+                metadata.Count.ShouldEqual(9);
 
                 // Only processes that have created placeholders since the last heartbeat should be named
                 metadata.ContainsKey("FilePlaceholderCreation").ShouldBeTrue();
@@ -202,6 +204,7 @@ public void GetMetadataForHeartBeatDoesSetsEventLevelToInformationalWhenPlacehol
                 metadata.ShouldContain("FolderPlaceholderCount", 1);
                 metadata.ShouldContain(nameof(RepoMetadata.Instance.EnlistmentId), RepoMetadata.Instance.EnlistmentId);
                 metadata.ContainsKey("PhysicalDiskInfo").ShouldBeTrue();
+                metadata.ShouldContain("IsSendingAnonymousRequests", true);
             }
 
             mockPlaceholderDb.VerifyAll();
diff --git a/GVFS/GVFS.Virtualization/FileSystemCallbacks.cs b/GVFS/GVFS.Virtualization/FileSystemCallbacks.cs
index 91e627dd2..c9fc1cd2a 100644
--- a/GVFS/GVFS.Virtualization/FileSystemCallbacks.cs
+++ b/GVFS/GVFS.Virtualization/FileSystemCallbacks.cs
@@ -292,6 +292,12 @@ public EventMetadata GetAndResetHeartBeatMetadata(out bool logToFile)
                     this.context.Enlistment.WorkingDirectoryBackingRoot,
                     sizeStatsOnly: true));
 
+            // True/false means "HttpRequestor is/isn't attaching an Authorization
+            // header to outgoing requests" (see HttpRequestor.cs), so a mount stuck
+            // reporting true for long stretches against a server that requires auth
+            // is the signature of the anonymous-auth-latch bug this field detects.
+            metadata.Add("IsSendingAnonymousRequests", this.context.Enlistment.Authentication.IsAnonymous);
+
             return metadata;
         }