The long legal war between Apple and Samsung reached the Supreme Court today. For the first time in a century, the high court considered what the limits of “design patents” should be.

Until they took up a starring role in Apple v. Samsung, design patents were like the poor, long-lost cousins of the better-known “utility” patents that cover machines themselves.

Here’s how this long-lasting technology case made its way to the high court: In 2012, the first Apple v. Samsung trial ended with a jury slapping Samsung with a $1.05 billion verdict for infringing Apple patents and trademarks. After appeals, that got whittled down to $548 million based entirely on patent infringement. With this Supreme Court case, Samsung is looking to get back the majority of that—the $399 million that’s based on three design patents.