The lawsuit is filed in District Court in Northern California.
It claims that Telegram did not take sufficient restrictive measures against users who disseminated extremist messages and calls for violence in connection with the riots in the Capitol on January 6.
The NGO believes that Telegram, by allowing the placement of such content, violates the terms of use of the Apple app store.
A similar claim is planned to be filed against Google.
Earlier, the founder of the messenger, Pavel Durov, said that the company's employees identified bots that spread rumors about the application on social networks. According to him, Facebook has a whole department where they are engaged in finding out the reasons for the popularity of Telegram.