The technology we use every day is built using thousands of lines of code — some of it written decades ago. Now, the Supreme Court is deciding when that code is free for others to use and when it is not. Back when Google was creating Android, the company decided to make it work with the popular programming language Java so it would be easier to make Android apps. But to do that, Google used Java code that is now owned by Oracle. Oracle sued, and several trials later, it’s in the Supreme Court’s hands. Amy Scott speaks with Mark Lemley, a law professor at Stanford University, where he teaches copyright and internet law.