diff --git a/client.c b/client.c
index 680647c05..924ad72ad 100644
--- a/client.c
+++ b/client.c
@@ -756,6 +756,9 @@ client_updatesizehints(client_t *c)
        && c->maxw == c->minw && c->maxh == c->minh)
         c->isfixed = true;
 
+    c->hassizehints = !(!c->basew && !c->baseh && !c->incw && !c->inch
+                        && !c->maxw && !c->maxh && !c->minw && !c->minh
+                        && !c->minax && !c->maxax && !c->minax && !c->minay);
     return size;
 }
 
diff --git a/structs.h b/structs.h
index 7ecc50984..cfd1b05f6 100644
--- a/structs.h
+++ b/structs.h
@@ -274,8 +274,10 @@ struct client_t
     area_t f_geometry;
     /** Max window geometry */
     area_t m_geometry;
+    /* Size hints */
     int basew, baseh, incw, inch, maxw, maxh, minw, minh;
     int minax, maxax, minay, maxay;
+    bool hassizehints;
     int border, oldborder;
     /** True if the client does not want any border */
     bool noborder;