Sharing Guidelines about Mastodon’s Trade Mark Policy

Recently, members of the community informed us that our Trade Mark Policy isn’t clear enough when it comes to when, where, and how servers and developers can use our brand name (Mastodon), particularly in the URL of a server. We heard you! Our team has worked to improve our Policy to make sure it is clear and fair to our community of server admins and developers.

We have updated our Policy to reflect these changes, but we also wanted to share them here with you. Please keep in mind that we have to balance our legal requirement to protect our Trade Marks with our desire to permit appropriate community use.

New guidelines for Trade Mark usage

This policy grants additional rights, and does not remove any rights that you have in law.

This policy applies only to uses of the Mastodon Trade Mark which are restricted, or reserved to Mastodon GmbH (the Trade Mark owner), by law. We are not intending to remove any rights that you have in law, only to grant additional rights (in certain circumstances).

Please do not use the Mastodon name or logo in a server’s, service’s, or product’s name or branding without our permission: To use the Mastodon name and logo as part of the name or branding (but not domain name or path; see below) of a server, service, or product, you must obtain express written permission from Mastodon GmbH. You can request permission by emailing legal@joinmastodon.org. We’ll consider requests on a case-by-case basis.

When we grant permission to use our Trade Mark, it will be on the condition that the server admin or developer include a prominent disclaimer: “This [server/site/project/product] is not affiliated with or endorsed by Mastodon GmbH or Mastodon Inc.”

We will reserve the right to revoke permission at any time and for any reason.

For servers running Mastodon software that want to use the Mastodon name in their top or second-level domain:

When a server is running Mastodon software (either unmodified or a derivative work of the Mastodon software), that server must not use the word “Mastodon” or confusingly similar names like “masto” or “mstdn” in the top or second-level domain name. The top and second-level domain names form the end of the full domain name, e.g. “example.com”. This restriction is because inclusion of “Mastodon” can confuse users as to whether or not that server is operated or endorsed by Mastodon GmbH. We want to institute this requirement to protect everyone involved. In an unfortunate case where we might need to revoke permission for you to use our Trade Mark, changing the URL of your server would require you to completely shut down your server and start over, and we don’t want that.

We also recognise that many servers running Mastodon software wish to include mastodon as a third (or deeper level) in their domain name, or as an identifier elsewhere in the URL for the server. This use is permitted, as long as it is not part of the top or second-level domain name.

Here are some specific examples to help illustrate what is permitted and what is forbidden:

• mastodon.example.com - Permitted
• example.com/mastodon - Permitted
• example.mymastodon.com - Forbidden
• example.masto.net - Forbidden
• example.best-mstdn-host.org - Forbidden

If your domain name uses “mastodon” (or a confusingly similar name) in a permissible way (as described above), we require that you include a disclaimer (in a footer or otherwise user-visible location) which states that “This [server/site] is not affiliated with or endorsed by Mastodon GmbH or Mastodon Inc.”

We also acknowledge that it would be burdensome for existing servers to change their domain name as a result of this new rule, so we are granting a special exception to affected servers with domain names using “mastodon” (or a confusingly similar name) that existed before May 13, 2026. This group of servers will be permitted to continue using their existing domain name, as long as they properly include the disclaimer as described above.

If you are not sure if your usage is appropriate, please reach out to us directly: legal@joinmastodon.org.

Let us know what you think

If you think we still need additional changes, we want to hear from you. Do these guidelines make sense? Are there edge cases or concerns we should consider? We’re committed to finding an approach that works for everyone.

Please share your feedback in the comments of this post, or reach out to us directly: legal@joinmastodon.org.

And finally, thank you to Neil Brown and others who assisted us with creating these guidelines!