There's a reason everyone hates printers. They break, jam, and always run out of cyan ink—which, inexplicably, also breaks them. Even when they work, toner costs so much you have to give up avocado toast for a month to buy more. As Matthew Inman, one of the great poets of his time, famously said: "Either printer ink is made from unicorn blood or we're all getting screwed."

WIRED OPINION About Kyle Wiens (@kylewiens) is the co-founder and CEO of iFixit, an online repair community and parts retailer.

Impression Products wanted to make toner a bit cheaper by refilling Lexmark printer cartridges. Lexmark of course hated that and sued. The fight dragged on for years, and made it all the way to the US Supreme Court. This week, the highest court in the land ruled against Lexmark. You may consider this an insignificant tussle over printer toner, but this important ruling clears the way for small businesses to fix your stuff—even without the manufacturer's permission.

As an added bonus, it should also help bring printer cartridge costs down. Good news for those of you who still print out Supreme Court decisions.

Impression v. Lexmark

Lexmark sells two kinds of cartridges: an expensive, reusable model; and a less expensive, single-use one. The only mechanical difference? The cheap cartridge features a chip that disables the damn thing once you refill it. Lexmark also made consumers sign a "post-sale restriction" contract stipulating that only Lexmark could collect, refill, and resell them.

Of course, people found a way around those constraints. Third-party companies collected cartridges and disabled the chip. Impression Products, a small, family-run office supply company in West Virginia, started selling refilled cartridges for less than Lexmark charged. Lexmark sued for patent infringement in 2013. Impressions CEO Eric Smith was baffled by the letters he received from Lexmark's attorneys. The way he saw it, his company was simply selling refurbished printer cartridges, and Lexmark had no right to control cartridges after selling them.

"I'm just a little guy who felt I was being bullied in the schoolyard," Smith told Ars Technica. "I decided to fight. Someone had to do it."

Raise the Stakes

Impression Products vs. Lexmark International hinged on two points: Did Impression infringe upon Lexmark's patents by (1) reselling cartridges in the United States when Lexmark explicitly prohibited reuse and resale, and (2) importing without authorization cartridges Lexmark sold abroad. Various courts split on these questions, and everyone from the AARP and Huawei to Costco and the Auto Care Association weighed in when the case finally reached the Supreme Court.

Why all the fuss? Because this wasn't really about printer toner. It was about your ownership rights, and whether a patent holder can dictate how you repair, modify, or reuse something you've purchased. "This case raises important questions about the reach of American patent law and how much control a manufacturer can exert after its products have been lawfully sold," the editorial board of The New York Times wrote in 2015. "Taken to their logical conclusion, Lexmark's arguments would mean that producers could use patent law to dictate how things like computers, printers, and other patented goods are used, changed, or resold and place restrictions on international trade."

Consider this: Countless people hack their Keurig machines to brew "unauthorized" coffee brands. Can Keurig sue them? Could Apple or Samsung stipulate that you can't resell their products on Craigslist or eBay? Could John Deere claim that a repair tech is infringing upon its patent rights by repairing a broken combine without permission? Consumer rights advocates at the EFF and Public Knowledge worried that a ruling in Lexmark's favor would "jeopardize independent product refurbishers and repair services".

This Time, It's Personal

The Supreme Court heard arguments in March and considered the principle of patent exhaustion. This idea stipulates that a patent owner's rights over a product should vanish once the patent owner sells the product to a consumer. By attaching a post-sale restriction to its single-use cartridge, Lexmark aimed to create a zombie patent that's never exhausted. You may have bought that cartridge, but Lexmark still controls it.

The justices agreed 7-1 that Lexmark can't do that. (Justice Neil Gorsuch was appointed after the court heard the case.) The court held that Lexmark exhausted its patent rights when it sold its cartridges "regardless of any restrictions the patentee purports to impose." To allow otherwise, the justices ruled, would adversely impact the economy.

"Take a shop that restores and sells used cars," chief justice John Roberts wrote in the majority opinion. "The business works because the shop can rest assured that, so long as those bringing in the cars own them, the shop is free to repair and resell those vehicles. That smooth flow of commerce would sputter if companies that make the thousands of parts that go into a vehicle could keep their patent rights after the first sale."

As it turns out, the Supreme Court is just as concerned about your right to repair as I am. No one besides the dealership would fix your car if it meant risking a patent lawsuit. And no one would touch your broken gadget either, because those devices are patented up the wazoo—a point Roberts made in his opinion, even if he didn't specifically say "wazoo."

Most consumer watchdog organizations roundly praised the decision. "Corporate restrictions on how products are used and resold are costly and onerous for consumers," says Public Knowledge. "The decision today largely puts a stop to that practice, at least with respect to patent law."

More Monsters

Although the court delivered a sound hit for David, the Goliath trying to deny you the right to repair isn't beaten yet. Corporations still employ many other ways of infringing on your rights.

With the Supreme Court issuing a definitive ruling on patent exhaustion, expect manufacturers to turn to contract law—like sneaky end user licensing agreements—to enforce their will. You already see it happening. John Deere, after losing a copyright law fight to folks like Repair.org, simply updated its EULA to block software modification in its tractors. Litigation dodged, problem solved. "They can't infringe upon your ownership rights if you've already signed them away," Gay Gordon-Byrne, director of Repair.org, told me.

Corporations will continue to do all they can to keep your ownership rights weak. It isn't personal, it's just business. But to a farmer relying on a EULA'ed tractor, it is quite personal. Let's hope an angry farmer takes his case to court. Or that right to repair legislation blocks these restrictive contracts. Otherwise, corporations will continue dictating what you can and can't do with the stuff you only think you own.

Kyle Wiens (@kylewiens) is the co-founder and CEO of iFixit, an online repair community and parts retailer. WIRED Opinion publishes pieces written by outside contributors and represents a wide range of viewpoints. Read more opinions here.