Development of Creative Commons licenses

[Gregor Hagedorn <g.m.hagedorn AT gmail.com>]

> This Public License is perpetual for the duration of the term of the
> underlying copyright or Copyright-like Rights licensed by Licensor. If You
> fail to comply with any condition of this Public License, this Public
> License terminates automatically, and You must obtain express approval from
> Licensor to use the Work thereafter.

(The relation between the duration of the condition "fail" and the
"thereafter" (during the duration of fail or also after the violation
is healed?) is still not clear to me as a non-native speaker. Your
answer implies that a kind of "life-imprisonment" away from CC is the
intention. If so:)

Since the licensors of a large fraction of CC BY-SA licensed works
cannot be contacted (what is the percentage of Wikipedia articles for
which ALL contributors can effectively be contacted?) and since this
fraction will drastically increase over time (what is the percentage
of Wikipedia authors from 2002 that are still active?), I think this
is undesirable.

License violations may well be unintended and in good faith. When
re-using Wikipedia-articles, parts of which have been copied from
other pages (with source page cited in the edit comment), it can be
very difficult to safely enumerate all authors.

I do not think a grace period is needed. The license should stop with
immediate effect.

However, I believe the solution would be to clearly state in the
license that it it possible to enter into a new public license
agreement or contract once the violation of the license is stopped.

Gregor