Sumpfweg 6
D-72070 Tübingen
phone: +49 (0)172-5621816

mail: info[at]

Managing director authorized to represent:

Dr. Tobias Heisig
Dr. Alexander Wittwer

Commercial register:

AG Stuttgart HRB 781420

Sales tax identification number according to § 27a Umsatzsteuergesetz

CIRCLE2 GmbH DE 347120054


Responsible in the sense of § 55 RStV:

Dr. Alexander Wittwer, Dr. Tobias Heisig (Anschrift wie oben)


General Terms and Conditions:

The General Terms and Conditions (GTC) of the company CIRCLE2 GmbH as of December 2021 apply.


Data Protection:

CIRCE2 GmbH takes the protection of your data very seriously.
For detailed information, please refer to our Privacy Policy..


Links and references:

At the time of linking, it was ensured that the referenced offers are free of illegal content. However, we have no influence on the current and future content changes of the respective provider and we expressly distance ourselves from any content changed after the link was set. The provider of the linked page is exclusively liable for this information as well as for any damage caused by it. As far as we get knowledge about the new illegal contents, the links or foreign entries will be deleted by us immediately. We request any notifications in this regard to be sent to the above address.



Texts, images, graphics, sound, animations and videos as well as their arrangement on the CIRCLE2 website are protected by copyright and other protective laws. The content of this website may not be copied, distributed, modified or made available to third parties for commercial purposes without express permission. The pages may also contain texts, images and other works that are subject to the copyright of third parties.


Concept and design:


Web development: