diff --git a/src/command_type.h b/src/command_type.h
index 0620b96b63..2419d7b312 100644
--- a/src/command_type.h
+++ b/src/command_type.h
@@ -349,7 +349,7 @@ enum DoCommandFlag {
 	DC_AUTO                  = 0x002, ///< don't allow building on structures
 	DC_QUERY_COST            = 0x004, ///< query cost only,  don't build.
 	DC_NO_WATER              = 0x008, ///< don't allow building on water
-	DC_NO_RAIL_OVERLAP       = 0x010, ///< don't allow overlap of rails (used in buildrail)
+	// 0x010 is unused
 	DC_NO_TEST_TOWN_RATING   = 0x020, ///< town rating does not disallow you from building
 	DC_BANKRUPT              = 0x040, ///< company bankrupts, skip money check, skip vehicle on tile check in some cases
 	DC_AUTOREPLACE           = 0x080, ///< autoreplace/autorenew is in progress, this shall disable vehicle limits when building, and ignore certain restrictions when undoing things (like vehicle attach callback)
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
index a714415326..34ad07d520 100644
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -263,12 +263,8 @@ static CommandCost CheckTrackCombination(TileIndex tile, TrackBits to_build, uin
 	}
 
 	/* Let's see if we may build this */
-	if ((flags & DC_NO_RAIL_OVERLAP) || HasSignals(tile)) {
-		/* If we are not allowed to overlap (flag is on for ai companies or we have
-		 * signals on the tile), check that */
-		if (future != TRACK_BIT_HORZ && future != TRACK_BIT_VERT) {
-			return_cmd_error((flags & DC_NO_RAIL_OVERLAP) ? STR_ERROR_IMPOSSIBLE_TRACK_COMBINATION : STR_ERROR_MUST_REMOVE_SIGNALS_FIRST);
-		}
+	if (HasSignals(tile) && future != TRACK_BIT_HORZ && future != TRACK_BIT_VERT) {
+		return_cmd_error(STR_ERROR_MUST_REMOVE_SIGNALS_FIRST);
 	}
 	/* Normally, we may overlap and any combination is valid */
 	return CommandCost();