diff --git a/st.c b/st.c
index aa4185c..836ae21 100644
--- a/st.c
+++ b/st.c
@@ -995,6 +995,8 @@ selnotify(XEvent *e) {
 
 	ofs = 0;
 	xsev = (XSelectionEvent *)e;
+	if (xsev->property == None)
+	    return;
 	do {
 		if(XGetWindowProperty(xw.dpy, xw.win, xsev->property, ofs,
 					BUFSIZ/4, False, AnyPropertyType,