> Google can still win this on fair use.

And, even if they lose on fair use, they can appeal the final ruling, including on the question here. There were arguments (including from the Solicitor General) that the Supreme Court should not take this case because the fair use question had not yet been addressed, so its perhaps premature to read into it whether the Supreme Court would take this question up, or how it would rule if it did, were the case otherwise finalized in the lower courts.

fwiw to @justonepost's point the wsj pointed out [1]:

"U.S. Solicitor General Donald Verrilli responded with a brief that urged the court to sidestep the case, particularly because the fair-use issue hadn’t been resolved in the lower court. Mr. Verrilli also said one of Google’s main arguments against copyrights on the Java packages was without merit."

Times like this when I miss groklaw.

[1] http://www.wsj.com/articles/supreme-court-denies-google-appe...

I hope that's the ultimate outcome. I'd be OK if we allow copyrighting of APIs as long as using those APIs falls under fair-use.

It would kind of defeat the point of publishing an API, wouldn't it? "Here's my API, but you can't use it without violating my copyright." Well, then, you might as well not have published it.

But the issue here is actually re-implementing the API, not calling it. The court could rule that an API could be copyrighted (and therefore freely called, but not freely re-implemented). The result would be that an API becomes a one-way interface. You couldn't have multiple competing implementations, you could only have one. That's still a big change for the software landscape...

How would APIs involving callbacks work? Would they need special license acrobatics to authorize you to implement a callback of the necessary form as specified by the copyrighted API?

You could have multiple competing implementations, they would for example either have to use the same header files provided by the copyright holder, implement a set of interfaces packaged in JAR file provided by the copyright holder (see JDBC as an example), or generate stubs from an IDL file provided by the copyright holder.