diff --git a/aegisub/src/subtitle_format.h b/aegisub/src/subtitle_format.h
index 8f7a84cdc..7c368a640 100644
--- a/aegisub/src/subtitle_format.h
+++ b/aegisub/src/subtitle_format.h
@@ -47,6 +47,8 @@
 #include <wx/string.h>
 #endif
 
+#include <libaegisub/exception.h>
+
 
 //////////////
 // Prototypes
@@ -161,3 +163,5 @@ public:
 };
 
 
+DEFINE_SIMPLE_EXCEPTION(SubtitleFormatParseError, agi::InvalidInputException, "subtitle_io/parse/generic")
+