https://en.wikipedia.org/wiki/The_Tetris_Company#Legal_enforcement

TTC drew attention in the late 1990s when it attempted to remove freeware and shareware clones of Tetris from the market by sending out cease-and-desist letters claiming both trademark and copyright infringement.[11] Creators of Tetris clones claimed that the company had no valid legal basis to restrict tetromino games that did not infringe on the Tetris name trademark, since copyright "look-and-feel" suits have not stood up in court in the past (Lotus v. Borland), and because the letters made no patent claims.[12]

In August 2008, Apple Inc. removed Tris, a clone of Tetris from its online App Store.[13] In March 2009, the Tetris Company sued BioSocia, operator of the Omgpop gaming portal[14][15] because one of its multiplayer games, Blockles, was too similar to Tetris. By September 2009, Omgpop removed the game from the website and replaced it with an alternate that the developers created, based on Puyo Puyo.

In May 2010, lawyers representing The Tetris Company sent Google a Digital Millennium Copyright Act Violation Notice regarding Tetris clones available on the Android Market.[16] Google responded by removing the 35 games listed in the notice even though, according to one developer, the games contained no references to Tetris.[17][18][19]

In February 2011, the Tetris Company continued to make copyright claims against independently developed Tetris clones, most notably against Tetrada on the Windows Phone 7 marketplace. The developer, Mario Karagiannis, rejected the claims of copyright infringement on the grounds that copyright does not cover gameplay design, but still removed the game, citing lack of resources to fight what he called "bullying".[20][21]

In the case Tetris Holding, LLC v. Xio Interactive, Inc., a US District Court judge ruled in June 2012 that the Tetris clone Mino from Xio Interactive infringed on the Tetris Company's copyrights by replicating elements such as the playfield dimensions and the shapes of the blocks.[22]

In April 2021, a YouTuber called JDH made an operating system that only runs Tetris.[23] Two months later, his GitHub repository was taken offline by The Tetris Company because of copyright infringement.[24][25]