[Someone]

I don’t understand the concern about database rights. OpenStreetMap is open (you can download it from https://planet.openstreetmap.org/), so why would they be concerned about copyrights?

[jaywalk]

I'd assume the main reason is because they require you to credit them when you're using their data: https://www.openstreetmap.org/copyright

[Doctor_Fegg]

Most open licences work by manipulating copyright. If you entirely relinquish the rights (a la CC0 or other "public domain" declaration), you can't enforce attribution or share-alike, which OSM wants to do.

[sigg3]

It doesn't manipulate copyright, it presupposes it.

The 'left' part of copyleft is about distribution or dissemination, and other rights bestowed. It doesn't challenge copyright at all.

You cannot grant rights for works without ownership, so PD has left the chat, so to speak.