diff --git a/man/systemd-sbsign.xml b/man/systemd-sbsign.xml
index 20cdf7f216..02d81c665d 100644
--- a/man/systemd-sbsign.xml
+++ b/man/systemd-sbsign.xml
@@ -75,7 +75,7 @@
         <listitem><para>Set the Secure Boot private key and certificate for use with the
         <command>sign</command> verb. The <option>--certificate=</option> option takes a path to a
         PEM-encoded X.509 certificate or a URI that's passed to the OpenSSL provider configured with
-        <option>--certificate-source</option>. The <option>--certificate-source</option> option takes one of
+        <option>--certificate-source=</option>. The <option>--certificate-source=</option> option takes one of
         <literal>file</literal> or <literal>provider</literal>, with the latter being followed by a specific
         provider identifier, separated with a colon, e.g. <literal>provider:pkcs11</literal>. The
         <option>--private-key=</option> option takes a path or a URI that will be passed to the OpenSSL