diff --git a/dwm.c b/dwm.c
index 4f345ee..8f4fa75 100644
--- a/dwm.c
+++ b/dwm.c
@@ -870,7 +870,8 @@ getatomprop(Client *c, Atom prop)
 
 	if (XGetWindowProperty(dpy, c->win, prop, 0L, sizeof atom, False, XA_ATOM,
 		&da, &di, &dl, &dl, &p) == Success && p) {
-		atom = *(Atom *)p;
+		if (dl > 0)
+			atom = *(Atom *)p;
 		XFree(p);
 	}
 	return atom;