I have a friend who competes in Rubik’s Cube championships. He can solve those puzzles with his hands (and feet!) in seconds, and you can watch his dizzying feats on YouTube.

A few weeks ago he received an email accusing him of ripping off a “unique 2x2x2 mechanism.” We’re not exactly sure what that phrase means. Could it mean that the e-mailer is laying claim to a particular method of solving the Rubik’s Cube? If the e-mailer was claiming a particular method of solving the Cube via a “2x2x2 mechanism,” they would have some precedent. There is, for instance, a patent for putting a golf ball (US 5776016A). Furthermore, baseball player Nolan Ryan also got a patent for his particular pitch, which includes the sentence, “The athlete stands on the starting pad and grips a suitable striking implement, such as a hand towel.”

Maybe the e-mailer was referring to the Cube itself—in which case, she or he would be but the latest of a long line of legal claimants surrounding the Rubik’s Cube. First, a bit of history: the Rubik’s Cube was invented in 1974 by Erno Rubik, a Hungarian professor of architecture. Rubik applied for a patent the following year under the name “Magic Cube.” By 1979, the Ideal Toy Corporation picked up the gadget and began selling it around the world with the moniker, “Rubik’s Cube.”

Here’s where things get sticky (cube pun not intended). When Rubik applied for a patent for his Magic Cube in Hungary (HU170062, which you can search for at the Hungarian Intellectual Property Office), he failed to apply for an international patent. Per the Paris Convention of 1883, someone getting a patent in one country has a year to file for patents in other countries to fully safeguard his or her invention.

And, unfortunately for Rubik, great minds think alike. In the United States, William Gustafson patented a spherical “manipulatable toy” in 1963 (US3081089). Another man named Larry Nichols had patented a 2x2x2 “Puzzle with Pieces Rotatable in Groups” in Canada two years before Rubik began to figure out his contraption. Nichols was also granted an American patent for his invention in 1972 (US3655201). Two years before that another inventor by the name of Frank Fox applied for a patent in the United Kingdom for an invention called the “Spherical 3x3x3” (1344259), and Terutoshi Ishige received a Japanese patent for a 3x3x3 in 1976 (55-819).

Nichols’ patent became quite a challenge. Moleculon Research Corp. obtained Nichols’ patent and sued the Ideal Toy Company several times in the 1980s. In the end, it came down to the fact that the Rubik’s Cube did not use a transitional step of “engaging eight cube pieces as a composite cube.” The courts granted that while the Ideal Toy Company’s 2x2x2 Pocket Cube may have infringed on Nichols’ puzzle patent, the 3x3x3 Cube that we know and love/hate was a valid patent.

To complicate matters, the Rubik’s Cube patent for its original mechanism has since expired. Seven Towns, which has since picked up the Rubik’s Cube, now preserves its rights to the puzzle with a trademark applied for in 1999 with Europe’s Office for Harmonization in the Internal Market (OHIM). This trademark dealt with the physical shape and structure of the cube. Its most recent challenge was last year, when the European Union court handed down a decision involving Seven Towns and Simba Toys. The latter, a German manufacturer, had tried to challenge the Seven Towns trademark by pointing out a distinction between the shape of puzzle and the 3-D ability to rotate aspects of the puzzle. Fortunately for Seven Towns, the court held that the Rubik’s Cube was distinctive enough in terms of its grid structure and its internal mechanism rotating capability from other 3-D puzzles that the patent was valid. In short, other companies can still make 3-D puzzles that shift and rotate—so long as they’re not shaped like the actual Rubik’s Cube and use the same rotation mechanism.

This case is part of the growing area of trademarks for 3-D objects, such as razor heads and Lego bricks. Lego, incidentally, lost their lawsuit—so many other manufacturers have used the 4×2 brick over the years that the judge ruled that it could not be trademarked as a form of art (happily for them, the figurines are still trademarked so everything is awesome on that front). To protect their 3-D trademark, Seven Towns is thus bringing legal action against a ton of other manufacturers from China to Israel on everything from the color of the tiles to the trademark itself.

This fight is for good reason. The cube, and the puzzle it poses, has continued to be immensely popular. It has been blamed for divorces and used in songs, college lectures on group theory, and Saturday Night Live skits. It’s the focus of no less than 212 Rubik’s Cube Competitions globally, according to the World Cube Association. People solve it whilst skydiving. In a twist (heh) of 3-D patent irony, one kid made a Lego robot to solve a Rubik’s Cube. The stakes (and stocks) are high.

You could say that there’s a Rubik’s Cube of legal issues surrounding the Rubik’s Cube. It’ll take more than a few seconds to solve, however, and more than a confused e-mail to leverage the situation.

Christine Chen is a J.D. candidate, ’17, at the NYU School of Law.