diff --git a/src/libnm-core-impl/nm-setting-ip4-config.c b/src/libnm-core-impl/nm-setting-ip4-config.c
index e9fb6d64e8..db1416483b 100644
--- a/src/libnm-core-impl/nm-setting-ip4-config.c
+++ b/src/libnm-core-impl/nm-setting-ip4-config.c
@@ -1143,6 +1143,13 @@ nm_setting_ip4_config_class_init(NMSettingIP4ConfigClass *klass)
      *          The default is <literal>unicast</literal>.</para>
      *      </listitem>
      *      <listitem>
+     *        <para><literal>"weight"</literal> - an unsigned 32 bit integer ranging from 0 to 256. This indicates
+     *          that the IPv4 route is a ECMP route and is only allowed for routes that specify a next-hop.
+     *          NetworkManager will automatically merge compatible routes into ECMP multi-hop routes.
+     *          Setting to zero or omitting the attribute configures single hop routes that won't get
+     *          merged. If the route finds no merge partner, it is configured as single hop route.</para>
+     *      </listitem>
+     *      <listitem>
      *        <para><literal>"window"</literal> - an unsigned 32 bit integer.</para>
      *      </listitem>
      *     </itemizedlist>