Add trademark hint to readme

(cherry picked from commit 1a0a2b34)

README.rst

@@ -4,7 +4,7 @@ AlekSIS (School Information System) — App كتاب السجل (class regis
 AlekSIS
 -------
 
-This is an application for use with the `AlekSIS`_ platform.
+This is an application for use with the `AlekSIS®`_ platform.
 
 Features
 --------
@@ -44,5 +44,13 @@ full licence text or on the `European Union Public Licence`_ website
 https://joinup.ec.europa.eu/collection/eupl/guidelines-users-and-developers
 (including all other official language versions).
 
+Trademark
+---------
+
+AlekSIS® is a registered trademark of the AlekSIS open source project, represented
+by Teckids e.V. Please refer to the `trademark policy`_ for hints on using the trademark
+AlekSIS®.
+
 .. _AlekSIS: https://edugit.org/AlekSIS/Official/AlekSIS
 .. _European Union Public Licence: https://eupl.eu/
+.. _trademark policy: https://aleksis.org/pages/about