diff --git a/examples/CMakeLists.txt b/examples/CMakeLists.txt
index 6ab6fb4b7d33037a60c42cd7f7ee056886ffb3fe..aec4b03aee28c6851ae04fe6b2538c8b28a8a184 100644
--- a/examples/CMakeLists.txt
+++ b/examples/CMakeLists.txt
@@ -60,7 +60,7 @@ dd4hep_enable_tests (
   DDG4_MySensDet
   DDCodex
   )
-if ( "${ROOT_VERSION}" VERSION_GREATER_EQUAL "6.20.00" )
+if ( "${ROOT_VERSION}" VERSION_GREATER_EQUAL "6.18.00" )
   dd4hep_enable_tests (
     OpticalSurfaces
     )