diff --git a/udev/udev.xml b/udev/udev.xml
index dc277c8918..b10096544b 100644
--- a/udev/udev.xml
+++ b/udev/udev.xml
@@ -359,7 +359,8 @@
           <term><option>ENV{<replaceable>key</replaceable>}</option></term>
           <listitem>
             <para>Set a device property value. Property names with a leading '.'
-            are not stored in the database or exported to external tool or events.</para>
+            are neither stored in the database nor exported to events or
+            external tools (run by, say, the PROGRAM match key).</para>
           </listitem>
         </varlistentry>