diff --git a/src/proxy.c b/src/proxy.c
index 3a9a4e4d5ba82971092e7be5dce1f4717678e4b8..ea82bcf8928cab9859427f052d88ee9d898f83c9 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -140,7 +140,7 @@ void proxy_addcell_in(struct proxy *p, struct cell *c, int type) {
     if (p->cells_in[k] == c) {
 
       /* Update the type */
-      p->cells_in_type[k] = type;
+      p->cells_in_type[k] |= type;
       return;
     }