Who Uses PF Today

PF has been ported from the original OpenBSD to the other BSDs, including

• FreeBSD

• NetBSD

• DragonflyBSD

• Apple's MacOSX, IOS (via FreeBSD)

• Blackberry (via NetBSD)

• Oracle, in Solaris 11.3 as one of two options, from Solaris 12 the only packet filter, replacing IPF, see this blog post and followups (also see my take).

Probably others (they don't need to actively advertise the fact)