Taking time and energy doesn't define copyright. There's tons of acts that take time and energy, and don't grant you a century long government backed monopoly on anything almost like it.
For instance, recipes, and tables of contents aren't copyrightable.
Going into case law, Sony v Bleem made it pretty clear that clean room reimplementations of APIs are on the table.
Going into US code, the otherwise crappy DMCA explicitly allows reverse engineering for interoperability. ie. interoperability even when the original vendor won't even tell you what the API is.
Going into practicalities, who owns SQL? Who owns POSIX?
The entire idea that APIs can have copyright is blatantly in contrast to decades of law, and is only happening because the CAFC is going off on it's own and ignoring 9th circuit precedent.
For those who would like more detail on this, the major case on this in the US is Feist Publications, Inc., v. Rural Telephone Service Co., 499 U.S. 340 (1991) [1].
This is not necessarily the case in other countries. See [2].
> The legality of the emulator is not at issue in this lawsuit.
> The issue in this appeal is the validity of the method by which Bleem is advertising its product.
> In various advertising media, Bleem has included comparative "screen shots" of Sony PlayStation games.
> We conclude that it is a fair use for Bleem to advertise comparatively only between what PlayStation games actually look like on a television and what they actually look like on a computer when played with the emulator.
For instance, recipes, and tables of contents aren't copyrightable.
Going into case law, Sony v Bleem made it pretty clear that clean room reimplementations of APIs are on the table.
Going into US code, the otherwise crappy DMCA explicitly allows reverse engineering for interoperability. ie. interoperability even when the original vendor won't even tell you what the API is.
Going into practicalities, who owns SQL? Who owns POSIX?
The entire idea that APIs can have copyright is blatantly in contrast to decades of law, and is only happening because the CAFC is going off on it's own and ignoring 9th circuit precedent.