--- a/xml/en/docs/http/ngx_http_upstream_module.xml
+++ b/xml/en/docs/http/ngx_http_upstream_module.xml
@@ -10,7 +10,7 @@
 <module name="Module ngx_http_upstream_module"
         link="/en/docs/http/ngx_http_upstream_module.html"
         lang="en"
-        rev="41">
+        rev="42">
 
 <section id="summary">
 
@@ -516,6 +516,34 @@ SCGI and uwsgi protocols do not have a n
 </directive>
 
 
+<directive name="ntlm">
+<syntax/>
+<default/>
+<context>upstream</context>
+<appeared-in>1.9.2</appeared-in>
+
+<para>
+Allows proxying requests with
+<link url="https://en.wikipedia.org/wiki/Integrated_Windows_Authentication">NTLM
+Authentication</link>.
+The upstream connection is bound to the client connection
+once the client sends a request with the <header>Authorization</header>
+header field value
+starting with “<literal>Negotiate</literal>” or “<literal>NTLM</literal>”.
+Further client requests will be proxied through the same upstream connection,
+keeping the authentication context.
+</para>
+
+<para>
+<note>
+This directive is available as part of our
+<commercial_version>commercial subscription</commercial_version>.
+</note>
+</para>
+
+</directive>
+
+
 <directive name="least_conn">
 <syntax/>
 <default/>