It seems I heard that header files are not considered copyrightable since they can only be written one way (like a list of ingredients or facts). So a header file for a specific DLL will always look the same when written in a given programming language. Unfortunately I can't find any resources to back this up.

So if a vendor provides an SDK with headers in one programming language, and then those headers are translated into another programming language by a third party. Does the 3rd party need permission from the vendor to provide the header translation? Who owns the copyright on the translation? Isn't it a derivative work still owned by the vendor, or is there no copyright, like a list of ingredients?

Does this vary from jurisdiction to jurisdiction?