If you encourage or openly tolerate the sharing of copyrighted materials, that is considered illegal and you can be sued for it. To be safe, discourage such activity. Instruct the community to post their own scripts or scripts they know to have been shared in the open - and then trust your community members to do the right thing. In a large community, you can't possibly police everything. So follow the YouTube example. If a developer or lawyer claims to own a script that one of your members is thought to have illegally posted, censor the file and inform the member. Ban repeat offenders.