diff --git a/src/ai/api/ai_object.cpp b/src/ai/api/ai_object.cpp
--- a/src/ai/api/ai_object.cpp
+++ b/src/ai/api/ai_object.cpp
@@ -10,7 +10,6 @@
 /** @file ai_object.cpp Implementation of AIObject. */
 
 #include "../../stdafx.h"
-#include <squirrel.h>
 #include "../../script/squirrel.hpp"
 #include "../../company_base.h"