diff --git a/qt6-after/qt6-migrated-legatus/docker_build.sh b/qt6-after/qt6-migrated-legatus/docker_build.sh
index 45c4dfd58..ba7c5b290 100755
--- a/qt6-after/qt6-migrated-legatus/docker_build.sh
+++ b/qt6-after/qt6-migrated-legatus/docker_build.sh
@@ -13,11 +13,20 @@ set -a
 source .envrc
 set +a
 
+# Allow BUILD_RTI to be overridden via environment variable or argument
+BUILD_RTI="${BUILD_RTI:-ON}"
+if [ "$1" = "OFF" ]; then
+  BUILD_RTI=OFF
+elif [ "$1" = "ON" ]; then
+  BUILD_RTI=ON
+fi
+
 # Run CMake configuration and build inside Docker
 docker run --rm \
   -e MIGRATE_PIPELINE_ROOT \
   -e LANG \
   -e LC_ALL \
+  -e BUILD_RTI \
   -v ${MIGRATE_PIPELINE_ROOT}:/workspace \
   -v ${MIGRATE_PIPELINE_ROOT}/rti_license.dat:/workspace/rti_license.dat \
   -w /workspace/qt-migration-legatus/qt6-after/qt6-migrated-legatus \
@@ -50,7 +59,7 @@ docker run --rm \
     cd build4
 
     cmake .. \
-      -DBUILD_RTI=ON \
+      -DBUILD_RTI=${BUILD_RTI} \
       -DBUILD_ARCGIS=OFF \
       -DCMAKE_CXX_STANDARD=17