Technology

Fun fact - GNU / FSF doesn't let you claim it's a GPL variant if you have added claims to it. If you say it's GPL then others gets to assume it's GPL proper

https://www.gnu.org/licenses/gpl-faq.html#ModifyGPL

You can legally use the GPL terms (possibly modified) in another license provided that you call your license by another name and do not include the GPL preamble, and provided you modify the instructions-for-use at the end enough to make it clearly different in wording and not mention GNU (though the actual procedure you describe may be similar).

If you want to use our preamble in a modified license, please write to licensing@gnu.org for permission. For this purpose we would want to check the actual license requirements to see if we approve of them.

Although we will not raise legal objections to your making a modified license in this way, we hope you will think twice and not do it. Such a modified license is almost certainly incompatible with the GNU GPL, and that incompatibility blocks useful combinations of modules. The mere proliferation of different free software licenses is a burden in and of itself.

As for attribution requirements;

https://www.fsf.org/blogs/community/gpl-compliant-legal-notices-author-attributions

However, requirements to preserve notices could conflict with user freedom.

Please note that "copyright notice" is a notice that contains: the word copyright (or the (C) symbol), the year of first publication of the work, and the name of the copyright holder. Any other information is not part of a copyright notice

In summary, people who modify programs released under the GNU GPLs can still change where and how an interactive program displays those notices. For example, if the original program put these notices at the bottom of every page, someone modifying the software could conceivably remove those and have them appear only on a single "About this software" page.

Apart from some specific situations, logos are neither "legal notices" nor "author attributions" as normally understood.

Putting trademarked links or logos in the program's interface and explicitly declining a trademark license thus gives the trademark holder a way to stop uses harmful to their reputation, balanced by the users' option to remove the trademarks in order to distribute modifications freely