Michael Snow wrote:
Requirements like that (the US used to
require a copyright notice) have been stripped away as an unreasonable
burden on authors.
I don't think that that was the reason. The publishers
would be the
ones to make sure that the notice was there anyway. Like abandoning the
requirement that registration was a precondition to copyright
protection, it was a consequence to acceding to international treaties
which demanded that copyright vest automatically in the author. The
author could not lose his rights out of ignorance.