Just a word of warning, the Tetris Company is pretty aggressive about protecting their trademarks. I'd at least pick a different name, but sometimes they even go after Tetris clones which don't use the name (e.g. Apotris).
The Tetris mark as a whole has an amazing history. It's a mark that was created from the ashes of a state that didn't allow trade and was involved in conflict and is kind of a marvel at the amount of cooperation that needs to happen for something like this. It's basically all edge cases.
Going after "clones" that have similar gameplay is wrong and they should (and likely do) know better. This has been resolved with Hasbro in the past as they were very litigious and went after clones of their games like Scrabble claiming their patent (and other parts) extended to the gameplay elements etc. IIRC the court rejected that argument and said that they can copyright or trademark the color combinations, names of points, etc. but they cannot patent the fundamental scrabble gameplay etc.
AIUI it's some weird legal sleight of hand where they don't (and can't) actually own the Tetris gameplay mechanics, but they have successfully argued in court that the appearance of the game constitutes their trade dress, and in practice you can't really implement the Tetris mechanics without the result looking like Tetris.
TTC is the gaming version of Oracle in that one meme[1], 90% of their raison d'etre is just to scare people away from making Tetris clones or variants without their permission so they can keep collecting rent on it forever.
Not just 'Tetris' (and *-'tris') trademark and Lanham Act trade dress, but they have also successfully argued in court [1] that the 'look and feel' of Tetris constitutes its copyrighted expression. In that case, Tetris Holding argued (and the judge agreed) that even the use of the seven one-sided tetromino playing pieces was part of their copyright.
Here's the description of the only Tetris gameplay mechanics the judge in this case conceded cannot be protected:
> Tetris is a puzzle game where a user manipulates pieces composed of square blocks, each made into a different geometric shape, that fall from the top of the game board to the bottom where the pieces accumulate. The user is given a new piece after the current one reaches the bottom of the available game space. While a piece is falling, the user rotates it in order to fit it in with the accumulated pieces. The object of the puzzle is to fill all spaces along a horizontal line. If that is accomplished, the line is erased, points are earned, and more of the game board is available for play. But if the pieces accumulate and reach the top of the screen, then the game is over. These then are the general, abstract ideas underlying Tetris and cannot be protected by copyright nor can expressive elements that are inseparable from them.
Disclaimer: I chose the colors from first principles and drew the graphics for Xio's version from scratch in Photoshop without any reference (as a volunteer; it was my friends' company), had to sit through depositions about this, etc.
In theory the Tetris Company is incorrect on the merits (the features they claim as "trade dress" are clear aspects of the game rules, not ornamentation, and in Xio's game had quite notable gameplay differences, especially in its multiplayer variants, and significant graphical style differences) and a discerning judge should see through the argument and find against them.
In practice judges often make a snap judgment based on personal prejudices (in this case, that the appearance amounted to "wholesale copying" that "pilfer[s] another's creativity" "without offering any originality or ingenuity of its own" and that such features as the way the pieces move falling from the top of the screen and the dimensions of the game board are "expression" rather than gameplay, and "Xio was also free to design a puzzle game using pieces of different shapes instead of using the same seven pieces used in Tetris." etc.) and ignore the letter and spirit of the law, filling in the decision starting from the conclusion. It has to date been too bothersome for someone with deep pockets to contest this to the appellate level.
I agree, the judgment read like a post hoc rationalization from someone unfamiliar with game development, uncritically parroting arguments of the side with a deeper bench.
What surprised me most from the ruling was how it took the legal doctrine of idea-expression dichotomy and twisted it into absurdity, hinging on an implicit argument that a game design essentially serves no utilitarian 'function' or 'purpose'. Core mechanics or essential gameplay rules like the tetrominoes or the 10-block width of the playfield are thus marked 'expression' or 'arbitrary flourishes', leaving a vague, unidentifiable abstraction of a falling-blocks puzzle game as the only unprotectible set of game rules that form its 'idea'.
Xio was free to design a puzzle game without tetrominoes, or downward+lateral+rotating movements, or a 10x20 playfield, and it would still 'function' just as well (that is: not at all, it's just a game). A chess game developer is equally free to design a strategy game without an 8x8 board or the knight's distinctive L-shaped movement, but it would no longer be chess, it would be rules for a completely different game.
Thanks, I thought the source had link-rotted but their server is just misconfigured (it looks like they switched from the www subdomain to a naked domain, but didn't set up a redirect, so old www links just throw an error).
I've always loved this image set. I have a feeling it's very different in 2025 though; would love to hear what current or very recent employees at these companies think
The name is the most important part, as it gives them a way to look for games that have their name but aren't theirs. But you're mostly right that they actually go after any game that has the same gameplay and is relatively popular, but only when they can easily issue a DMCA takedown. It's not like they ever said that this was their policy but you can see it bear out time and again.
TETR.IO and Jstris are insanely popular games that have been up for years with no action against them since they aren't hosted on another platform/marketplace.
This is also why Apotris got 2 DMCA takedowns on both Github and itch.io 3 months apart from each other, but after hosting the game on my own site, they haven't taken any further action in the past 2 years while it has continued to grow in popularity.
The shapes are called tetrominos, four squares connected orthogonally. Tetris the game, was created with pentominoes (5 squares) and scaled down to tetrominos. The game was inspired by physical puzzles where fill a rectangle with the shapes. So these shapes existed before Tetris.
Would they go after the shapes? Possibly. See "Tetris Holding, LLC v. Xio Interactive, Inc.".
Which is crazy, because the shapes are just an idea, and you can't copyright ideas. They also couldn't be a trademark infringement (IANAL, though) if you don't use them in your branding.
They can go after you for anything. Whether or not that would hold in court is a separate question, but they count on the fact that you would be probably unwilling to test it.
It is the series of shapes in one project that makes it Tetris. So think of it as a series of copied ideas in one product that make it a legal challenge
They don't claim copyright on the mechanics. They pursue trademark violation. If it has falling tetrominos, it might be confused with Tetris, is the idea. You can use different shapes and be fine.
I could imagine the specific combination where the shapes colors match the original could get into trademark territory, as the colors have no in-game requirement to be those specific values.
https://github.com/github/dmca/blob/adcac3eddac2e5555d87942d...