diff --git a/include/ts/apidefs.h.in b/include/ts/apidefs.h.in
index 49f5a83cd0b..7d976012eb3 100644
--- a/include/ts/apidefs.h.in
+++ b/include/ts/apidefs.h.in
@@ -196,6 +196,7 @@ typedef enum {
   TS_HTTP_STATUS_PRECONDITION_REQUIRED           = 428,
   TS_HTTP_STATUS_TOO_MANY_REQUESTS               = 429,
   TS_HTTP_STATUS_REQUEST_HEADER_FIELDS_TOO_LARGE = 431,
+  TS_HTTP_STATUS_UNAVAILABLE_FOR_LEGAL_REASONS   = 451,
   TS_HTTP_STATUS_INTERNAL_SERVER_ERROR           = 500,
   TS_HTTP_STATUS_NOT_IMPLEMENTED                 = 501,
   TS_HTTP_STATUS_BAD_GATEWAY                     = 502,