Formlabs made history last month when it raised $2.95 million for its Form 1 3D printer on Kickstarter. The successful funding means the affordable 3D printer will make high-quality 3D printing possible for even more people. Well, that was the case at first, but now the startup is being threatened by a patent lawsuit.

BBC reports that 3D Systems, a 3D printer manufacturer, has filed suit against Formlabs and Kickstarter over a patent the company was awarded in 1997. The patent covers a specific innovation in stereolithographic 3D printing that prevents 3D printed models from falling apart. Now 3D Systems says that Formlabs infringed upon its patent.

So why is Kickstarter being sued as well? For one, Kickstarter profited from the success of the Form 1 by taking its usual five percent cut of the entire proceeds raised. 3D Systems also says that by promoting the Form 1, Kickstarter has caused them “immediate and irreparable injury and damage.”

Unlike the usual patent trolls that dominate the tech industry, 3D Systems actually has a case here. They even have Formlabs co-founder Maxim Lobovsky on record saying they were able to offer the Form 1 so cheaply because a number of patents had expired.

So, either Formlabs didn’t know about 3D Systems’ patent, or they just ignored it. Either way, the startup is now going to have to deal with a patent lawsuit that may bar them from being able to produce the Form 1 for backers. After raising almost $3 million, it would be a real bummer to not see the Form 1 become a reality.