diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 4ee39f675..93b429087 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -116,6 +116,8 @@ function(add_impactx_test name input is_mpi analysis_script plot_script)
     else()
         set_property(TEST ${name}.run APPEND PROPERTY ENVIRONMENT "OMP_NUM_THREADS=2")
     endif()
+    # special return code for skipped tests (e.g., runtime prerequisite fails)
+    set_tests_properties(${name}.run PROPERTIES SKIP_RETURN_CODE 42)
 
     # analysis and plots
     set(THIS_Python_SCRIPT_EXE)
diff --git a/examples/pytorch_surrogate_model/run_ml_surrogate_15_stage.py b/examples/pytorch_surrogate_model/run_ml_surrogate_15_stage.py
index 5a9bb8bdb..85d62fbc2 100644
--- a/examples/pytorch_surrogate_model/run_ml_surrogate_15_stage.py
+++ b/examples/pytorch_surrogate_model/run_ml_surrogate_15_stage.py
@@ -37,7 +37,7 @@
     print("Warning: Cannot import PyTorch. Skipping test.")
     import sys
 
-    sys.exit(0)
+    sys.exit(42)  # ImpactX special return code for skipped tests
 
 import zipfile
 from urllib import request