I'm not sure the "API is copyrightable" argument was relevant in the Microsoft-Sun case. Keep in mind that case was settled privately. Since it was never decide

I'm not sure the "API is copyrightable" argument was relevant in the Microsoft-Sun case. Keep in mind that case was settled privately. Since it was never decided in court, it's hard to say what the most relevant claims were, but I don't see Sun making much of the copyright claim. They had a licensing claim because they claimed Microsoft had licensed the Java trademark but was not implementing it fully according to the spec. That seems rather different than this case.