diff --git a/libaegisub/include/libaegisub/option_value.h b/libaegisub/include/libaegisub/option_value.h
index 152993c47..6cf960597 100644
--- a/libaegisub/include/libaegisub/option_value.h
+++ b/libaegisub/include/libaegisub/option_value.h
@@ -25,7 +25,6 @@
 
 namespace agi {
 DEFINE_BASE_EXCEPTION_NOINNER(OptionValueError, Exception)
-DEFINE_SIMPLE_EXCEPTION_NOINNER(OptionValueErrorNotFound, OptionValueError, "options/not_found")
 DEFINE_SIMPLE_EXCEPTION_NOINNER(OptionValueErrorInvalidType, OptionValueError, "options/invalid_type")
 
 /// Option type