Mastodon Lawyers Tell Trump Social Network to Make Source Code Public

Mastodon said it sent a formal letter to 'Truth Social' after media reports found the site was using Mastodon's codebase while not respecting a part of its software license.
Trump and Mastodon
Image: Sean Rayford/Stringer, Mastodon

Lawyers for the social network codebase Mastodon have sent a formal letter to former President Donald Trump’s upcoming social network ‘Truth Social’ asking the site to make its source code publicly available, according to an announcement from Mastodon today. The move comes after Mastodon’s founder Eugen Rochko told Motherboard that Truth Social is using Mastodon code without respecting the terms of the software’s license.


“On Oct 26, we sent a formal letter to Truth Social’s chief legal officer, requesting the source code to be made publicly available in compliance with the license. According to AGPLv3, after being notified by the copyright holder, Truth Social has 30 days to comply or the license may be permanently revoked.” the announcement reads.

Rochko shared a copy of the letter with Motherboard.

“Based on public reports, we understand that Truth Social used Mastodon’s

source code to develop its platform and that users were able to connect with the platform over a network. Accordingly, under the AGPL, Truth Social is required to make its complete source code available. We request that Truth Social comply with this important condition of the license,” it reads. “If you have questions regarding Mastodon or the AGPL, please feel free to contact us,” it adds.

Do you know anything else about Truth Social? We'd love to hear from you. Using a non-work phone or computer, you can contact Joseph Cox securely on Signal on +44 20 8133 5190, Wickr on josephcox, or email

Truth Social describes itself as “America’s ‘Big Tent’ social media platform that encourages an open, free, and honest global conversation without discriminating against political ideology” on its website. Its terms of use say that “all source code” of Truth Social is proprietary.


That is not true, however: when sections of the site went live earlier this month, users quickly found clear use of Mastodon code on Truth Social. The HTML for the Truth Social login screen mentioned Mastodon explicitly, and Rochko told Motherboard that screenshots of the site looked “exactly like the Mastodon UI with the light theme.”

Mastodon itself is a piece of open-source software that people can use as a base to make their own social networks. Largely anyone, including Truth Social, is able to use the code. But its license requires those who do to in turn make their source code and any modifications available to the public, Rochko previously told Motherboard. The letter suggests that Truth Social has not done that, and thus may be in violation of the terms of the license.

Trump Media & Technology Group, the company behind Truth Social, did not immediately respond to a request for comment on whether it has received the letter or whether it intends to make Truth Social’s source code public. Neither did the legal contact for Truth Social itself.

Last week the SPAC stock connected to Truth Social skyrocketed last week before sharply dropping in price on Monday, CNBC reported.

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