The U.S. Supreme Court on Monday declined to hear Google Inc's appeal in a major software copyright case, leaving intact a ruling that would allow Oracle Corp to charge licensing fees for the use of some of its Java programming language.

The high court left in place a May 2014 ruling by the U.S. Court of Appeals for the Federal Circuit in favor of Oracle. Google had argued it should be free to use Java without paying a licensing fee.

The case involved how much copyright protection should extend to the Java programming language.

Google, which used Java to design its Android smartphone operating system, said in court papers that an Oracle victory would obstruct "an enormous amount of innovation" because software developers would not be able to freely build on each others' work.

Oracle said effective copyright protection is the key to software innovation.

The Obama administration, asked to weigh in on the issue earlier this year, asked the court not to take the case.

The case is Google v. Oracle, U.S. Supreme Court, No. 14-410.

(Reporting by Lawrence Hurley; Editing by Will Dunham)