Most of the world's smartphones run on Google's Android software. But did Google play fairly when it created that software?
That question is at the heart of a case being argued in front of the U.S. Supreme Court on Wednesday. It's the culmination of a battle that started 10 years ago, when tech company Oracle first accused Google of illegally copying its code.
The code in question is about 11,000 lines, accounting for less than 0.1% of the 15 million lines that make up Android software. Google used parts of a software called Java, owned by Oracle, in those 11,000 lines — without paying any licensing fee. Now, Oracle says Google owes it nearly $9 billion in damages, given the ubiquity and success of Android.
"Google was essentially offering a competing product and using our software in that competing product and giving it away for free. So it's really hard to compete with that," Dorian Daley, Oracle's top lawyer, told NPR.
Google argues that no one should be allowed to claim ownership of this kind of code. "This has been the settled understanding of the application of copyright to software ever since we've been developing software," said Kent Walker, Google's senior vice president of global affairs.
Given how dry and highly technical discussions of code inevitably are, it's no surprise that both sides have turned to metaphor to make their arguments.
Oracle's preferred analogy, which it has used in its legal filings, is to the Harry Potter book series. It says what Google has done is like taking key parts of those books — chapter titles, character names, the first sentence of each paragraph — writing a new book, and selling it.
"Those would clearly be protected under copyright law," Daley said. "It simply wouldn't be fair for a copyist to copy all of that, write another book for commercial gain and impact the market for the original."
But Google's supporters say that metaphor is all wrong.
"The more apt analogy would be the structure of the book itself," like the spine and numbered pages, said Robert Cheetham, founder and CEO of Azavea, a small software company in Philadelphia. "It's the mechanism for accessing and using that book that is the interface for not just Harry Potter, but all books."
Cheetham sides with Google in this fight. He says what Google did by using Java is simply how software is made: developers rely on using certain bits of code to build their programs.
Google lawyer Walker said the code in question is key to making software work across apps and devices. "It's what lets you take a picture using an iPhone stored in Google Photos and edit it on a Microsoft laptop," he said.
The case poses two big questions for the Supreme Court, said Tejas Narechania, assistant professor of law at the University of California, Berkeley.
"The first is, do the copyright laws even extend to this sort of expression?" he said. In other words, does Oracle's code get the same copyright protection as a Harry Potter book?
"The second question is, even if Oracle can claim that sort of protection ... whether it's fair use for Google to use [the code]," he said. The answer to that will depend on how the justices interpret the intricacies of copyright law.
However the court rules, it will have an impact well beyond the wealthy tech giants.
The entertainment and publishing industries, which rely on copyright protection, as well as smaller companies in Silicon Valley and beyond are watching the outcome closely.
Those who back Google say if Oracle wins, it will be more expensive and difficult for small companies to compete.
"It makes big companies stronger, it gives them more leverage over startups and other new businesses that are trying to compete against incumbents," Cheetham said
Those in Oracle's camp say if its copyright is not protected, that will discourage innovation.
"There's a lot of small start-up companies in the software space, some of whom rely ... on the copyrightability and the copyright protection that goes with the Copyright Act to justify their business model," said Bob Taylor, a Silicon Valley lawyer who works with start-ups and investors.
"It's much easier to copy software than it is to develop it," he said.
Editor's note: Google and Oracle are among NPR's financial supporters.