[dragonwriter]

> So how do you tell the difference between the files having been licensed individually or only the whole compilation having been licensed?

One way you could check is if each of the files has their own copyright and license notice, and the license notice includes, directly or by reference, terms which require preservation of the accompanying copyright notice.

[shawnz]

How can you be sure the license notice wasn't meant to apply to the project as a whole, as I imagine is overwhelmingly the more common intention? That is the obvious question here.