diff --git a/src/openttd.h b/src/openttd.h
--- a/src/openttd.h
+++ b/src/openttd.h
@@ -45,6 +45,7 @@ enum DisplayOptions {
 	DO_FULL_ANIMATION      = 3, ///< Perform palette animation.
 	DO_FULL_DETAIL         = 5, ///< Also draw details of track and roads.
 	DO_SHOW_WAYPOINT_NAMES = 6, ///< Display waypoint names.
+	DO_SHOW_COMPETITOR_SIGNS = 7, ///< Display signs, station names and waypoint names of opponent companies. Buoys and oilrig-stations are always shown, even if this option is turned off.
 };
 
 extern GameMode _game_mode;