The culmination of many years of litigation between Google and Oracle. At issue was Google’s copying of 11,500 lines of code of the Java SE API. The US Supreme Court declared it fair use.
The case highlights the relatively weak protection that copyright offers for computer programs. The functional aspects of a computer program are better protected by patent than copyright.
Fair use is a murky concept, though. Computer programs still get copyright protection and it is still important to protect them.