I'd say that licenses like BSD and Artistic are less encouraging to contribute back than say GPL but it is more a problem for module authors then for their end users and your example shows it. In the context of this
thread it is definetely is not a problem.
As for corporate legal may find that verifying this is harder than they want: well, in this case you should not use Perl in first place as Perl itself and all core modules are dual licensed under GPL/Artistic.
Ilya Martynov, firstname.lastname@example.org
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