Creativity and innovation do not occur in a vacuum. The greatest songs, movies, and art are frequently at least inspired by and sometimes borrow heavily from predecessors and contemporaries. Software is no different. For this reason, today, we filed an amicus brief with the Federal Circuit advocating that the implementation of APIs should be considered a fair use under U.S. copyright law.

The story of the technology at stake in Oracle v. Google is about interoperability. When Google created the Android smartphone environment, it wanted to ensure that developers accustomed to writing Java-based software could immediately develop software for Android. To achieve this compatibility, Google used the “declaring code” of 37 Java API packages and implemented them with its own code.

Years later, shortly after it acquired Sun Microsystems and the Java platform, Oracle sued Google for copyright infringement. In 2014, the Federal Circuit Court of Appeals held that the declaring code and “structure, sequence, and organization” of the Java APIs were subject to copyright. We had filed a joint amicus brief, in that case, advocating for the opposite conclusion and were disappointed by the Court’s decision. Since then, the outstanding question has been whether Google’s use of the declaring code is nevertheless a fair use. Despite a jury unanimously deciding ‘yes’ last year, Oracle is arguing on its second appeal that the law requires the answer always be ‘no’.

Fair use is essential for software: it allows for new and creative re-implementations of code and is critical for interoperability between technologies and systems. Mozilla has been a consistent advocate for the importance of fair use rights, so much so that even the Mozilla Public License explicitly acknowledges that it “is not intended to limit any rights” under applicable copyright doctrines such as fair use. We hope that the Federal Circuit will recognize the value of fair use, and reach a decision that allows it to continue to play an important role in software innovation.