diff --git a/client/displayservers/X11/clipboard.c b/client/displayservers/X11/clipboard.c
index 967f7dbd..2387c28f 100644
--- a/client/displayservers/X11/clipboard.c
+++ b/client/displayservers/X11/clipboard.c
@@ -76,6 +76,9 @@ bool x11CBEventThread(const XEvent xe)
       return true;
 
     case PropertyNotify:
+      if (xe.xproperty.state != PropertyNewValue)
+        break;
+
       if (xe.xproperty.atom == x11atoms.SEL_DATA)
       {
         if (x11cb.lowerBound == 0)