diff --git a/tree.c b/tree.c
index 2130d55..d2347df 100644
--- a/tree.c
+++ b/tree.c
@@ -4558,6 +4558,7 @@
     if (doc == NULL) return(NULL);
     ret = xmlNewDoc(doc->version);
     if (ret == NULL) return(NULL);
+    ret->type = doc->type;
     if (doc->name != NULL)
         ret->name = xmlMemStrdup(doc->name);
     if (doc->encoding != NULL)