Just in case I might need it some day ... is there a place where I can inform the Magento guys of a license validation? Searched a bit but found nothing.
Thanks
Your search may have resulted in nothing useful because of the way you are asking and wording this question. If you are asking about Magento Enterprise (now known as Magento Commerce) licensing verification, as in, double-checking with Magento that a website or copy of the software is adhering to the legality of the licensing terms, or within the terms of licensing agreements, first check out the licensing documents:
https://magento.com/legal/terms
If the software is 'enterprise' versioned, then it comes with a LICENSE_EE.txt file, which will answer your questions or at least give you an idea of how to proceed.
UPDATE
Solution, based on your newly added comments: https://magento.com/legal/licensing
That URL contains the details surrounding these topics: Magento License / Trademarks FAQs
The URL posted originally, https://magento.com/legal/terms, would be the best place to start, though.