Straightforward "copyright" is the license corresponding to "all rights reserved". However, works can have "Copyright © [year] [name]" on them without being ARR. A work under, say, a CC-BY license is under the copyright of its author, who has simply chosen to have laxer restrictions on reuse than one's rights under the Berne Convention. Due to said convention, there's no actual need to declare a work "all rights reserved" -- this is the default assumption in all Berne signatory countries, which is "virtually all of them".
In theory, an interesting test case could come out of "author labels work as ARR, unintentionally uploads under non-ARR license on a repository, someone reuses it by its accidental license". I suspect variants of this have already happened by way of Wikimedia Commons, which gets 1. a lot of drive-by uploads by people who don't understand its licensing and 2. a lot of massive database scrapes and image resales by people who do.
As a total aside, "three different PD or PD-equivalent licenses" on that list seems a bit much.