diff --git a/defines.h b/defines.h
index b4ef99e..7357874 100644
--- a/defines.h
+++ b/defines.h
@@ -20,7 +20,7 @@
 #define SSOCR2_DEFINES_H
 
 /* version number */
-#define VERSION "2.13.0"
+#define VERSION "2.13.1"
 
 /* states */
 #define FIND_DARK 0