Z:gnu-www-ja-common-distros--a74fc8-Slackware has the two usual pr/en

Slackware has the two usual problems: there's no clear policy about what software can be included, and nonfree blobs are included in Linux, the kernel. It also ships with the nonfree image-viewing program xv. Of course, with no firm policy against them, more nonfree programs could get in at any time. There is an unofficial list of nonfree software in Slackware.