Wordle Archive—a website that let users play through hundreds of previous daily five-letter Wordle puzzles—has been taken down at the request of Wordle owner The New York Times.

The archival site, which offered a backward-looking play feature that’s not available in the NYT’s official version of Wordle, had been up since early January. But it was taken down last week and replaced with a message saying, “Sadly, the New York Times has requested that the Wordle Archive be taken down.” A Twitter search shows dozens of daily Wordle Archive players who were willing to share their results on social media up through March 7.

“The usage was unauthorized, and we were in touch with them,” a New York Times representative said in response to an Ars Technica comment request. “We don’t plan to comment beyond that.”

The Wordle Archive is still fully playable in its own archived form (as of March 5) at the Internet Archive, appropriately enough. Other sites that allow you to play archived Wordle puzzles are not hard to find, as are sites that let you play unlimited Wordle puzzles beyond the usual one-a-day limit.

But some of those sites may be under threat, if the Times’ treatment of Wordle Archive is any indication.

Are any clones safe?

The basic five-letter guessing game underlying Wordle is not itself a completely original idea. The concept was widely popularized by Lingo, a game show that dates back to the ’80s in the US and other countries. The two-player pen-and-paper game Jotto, which dates back to 1955, would also be very familiar to Wordle players. Before that, a more traditional version of the game called Bulls and Cows has been played since the 19th century, according to at least one source.

Even if that prior art didn’t exist, though, The New York Times would have trouble claiming copyright protection on the basic design of Wordle. While Wordle‘s specific presentation can be copyrighted, the game’s basic guessing mechanic is hard to protect with anything short of a patent (which would be exceptionally hard to acquire, in this case).

“Whenever you have a copyright, you’re protecting the expression, not the idea,” Dallas attorney Mark Methenitis told Ars. “It’s a line a lot of people have a very hard time with, especially when you get into games.”

The Times’ interest in Wordle is less ambiguous when it comes to trademark, which protects the game’s name and branding. The New York Times filed for a Wordle trademark on February 1, the day after the paper announced its seven-figure purchase of the game from original creator Josh Wardle.

That means the company can go after any other product that uses the Wordle name directly, especially if there’s a substantial risk that an average user might confuse it with an official Times product. Plenty of other web games capitalizing on the Wordle name are out there, as well as spin-offs like Crosswordle that integrate the Wordle trademark.

Other games that use the “-dle” suffix to connote broad Wordle similarities—a la Windle, Nerdle, or Worldle—aren’t completely in the clear either. The Tetris Company has brought trademark lawsuits against games with names that are only similar to the original Tetris. And that’s to say nothing of games that copy Tetris‘ gameplay and presentation outright, showing there is a level of direct game cloning that a court won’t tolerate.

In January, before the NYT acquisition, Apple purged a number of blatant Wordle clones from the iOS App Store after those clones received negative social media attention. Section 4.1 of the iOS App Store guidelines specifically call out “copycats,” telling developers directly to “come up with your own ideas. We know you have them, so make yours come to life. Don’t simply copy the latest popular app on the App Store or make some minor changes to another app’s name or UI and pass it off as your own.” But those restrictions didn’t necessarily apply directly to Wordle, which exists as a web game and not a native iOS app.

While Wordle remains free to play and separate from the Times’ popular Games subscription plan, the company hasn’t committed to the game’s long-term status. “We don’t have set plans for the game’s future,” a Times spokesperson told Ars. “We’re focused on continuing to make Wordle a great daily puzzle.”