diff --git a/Tracking/TrkAlgorithms/TrkTruthAlgs/TrkTruthAlgs/ATLAS_CHECK_THREAD_SAFETY b/Tracking/TrkAlgorithms/TrkTruthAlgs/TrkTruthAlgs/ATLAS_CHECK_THREAD_SAFETY
new file mode 100644
index 0000000000000000000000000000000000000000..7ab038a4a9c1c2c5c2d6ba216f04c11af0ce43f5
--- /dev/null
+++ b/Tracking/TrkAlgorithms/TrkTruthAlgs/TrkTruthAlgs/ATLAS_CHECK_THREAD_SAFETY
@@ -0,0 +1 @@
+Tracking/TrkAlgorithms/TrkTruthAlgs