On Sun, 23 Aug 2015, Thorsten Alteholz wrote: > But policy says that there "should" be such a copyright file. Violating such a > clause is at least an important bug.
I guess you refer to policy when it says that we could match "must" with "serious" and "should" with "important". However, the BTS documentation says that important means "a bug which has a major effect on the usability of a package, without rendering it completely unusable to everyone". Not having a debian/copyright file in the source package does not affect usability of the package in *any* way. So: Why is this a "should" at all?
