Oracle v. Google
The decade-long US lawsuit over whether reusing Java's API declarations in Android was copyright infringement.
Oracle bought Sun in 2010 and sued Google the same year. Android had recreated 37 of Java's standard packages – its own implementation, but the same declarations: some 11,000 lines describing what the methods are called and which arguments they take. Oracle eventually sought around nine billion dollars. The patent claims collapsed early, as did the much-discussed nine-line rangeCheck function.
Judge William Alsup, who learned Java during the proceedings, ruled in 2012 that APIs weren't copyrightable. The Federal Circuit reversed in 2014, a jury found fair use in 2016, and the Federal Circuit reversed again in 2018. In April 2021 the Supreme Court sided with Google 6–2 on fair use. It deliberately left open whether APIs are copyrightable at all, so the industry still rests on a ruling about the exception rather than the rule.