diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 899e4c8..d2e933a 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -6457,6 +6457,7 @@
 ex_preserve(eap)
     exarg_T	*eap;
 {
+    curbuf->b_flags |= BF_PRESERVED;
     ml_preserve(curbuf, TRUE);
 }