No they aren't, but there is such a thing as a database right which is separate from copyright. This is why OSM changed from a Creative Commons licence (a copyright licence) to ODbL (a database licence).

> but there is such a thing as a database right which is separate from copyright

That's purely an unforced error on the part of OpenStreetMap. They are incorporated in England, which recognizes a database right. But there is no reason for that. In general, there is no such thing as a database right.

And this isn't even relevant to londons_explore's point; he is stupidly arguing that even if the information is available on a road sign, the public cannot use it because it might be included in a protected work somewhere. That is obviously untrue; the availability on the road sign does in fact automatically mean that inclusion in a protected work is irrelevant.

If you see a sign giving you the name of a road, and then publish information to the effect that the road's name is what is printed on that sign, no database was involved at any point, and a database right cannot apply. All you have is a bare fact.