diff --git a/expat/xmltok/xmltok_impl.c b/expat/xmltok/xmltok_impl.c
index db6cc1ab..cc64e959 100755
--- a/expat/xmltok/xmltok_impl.c
+++ b/expat/xmltok/xmltok_impl.c
@@ -1007,7 +1007,7 @@ int PREFIX(prologTok)(const ENCODING *enc, const char *ptr, const char *end,
   case BT_RPAR:
     ptr += MINBPC;
     if (ptr == end)
-      return XML_TOK_INVALID;
+      return XML_TOK_PARTIAL;
     switch (BYTE_TYPE(enc, ptr)) {
     case BT_AST:
       *nextTokPtr = ptr + MINBPC;