The BUNDLE_LIBRARY_OUTPUT_DIRECTORY is set to LIBRARY_OUTPUT_PATH which is set to CMAKE_BINARY_DIR/bin

My understanding is that the oce dll's are installed into CMAKE_RUNTIME_OUTPUT_DIRECTORY which is a configurable variable that can be different from CMAKE_BINARY_DIR/bin. The removed line ensured that the bundle dll's are installed in the same place as the oce dll's, namely CMAKE_RUNTIME_OUTPUT_DIRECTORY.