Copyright permission is the only mechanism that almost unambiguously is required to maximize social value realized from sharing and collaboration around intangible goods (given that copyright exists):

• Some people think the addition of conditions that are in effect non-copyright regulation are also required, but others disagree, and given widespread ignorance about and noncompliance with copyleft regulation, I put in the class of probably important (is there anyone conducting serious research around this question?) rather than that of unambiguously required. In any case, current copyleft conditions would be nonsensical if not layered on top of permissions.
• I’ve heard the argument made that no mechanism is needed: culture aided by the net will route around copyright and other restrictions, just ignore them. I can’t find a good example, but some exhortations and the like of copyheart and kopimi are a subset of the genre. But unless one can make the case that the participation of wealthy litigation targets (any significant organization, from IBM to Wikimedia) is a net negative (and that’s only the first hurdle for such an argument to clear), a mechanism for permissions that appear legally sound to the copyright regime seem unambiguously necessary.
• There are lots of other real and potential restrictions that permission can and may be possible to grant around, but so much progress has been made with only copyright permissions explicitly granted, and how other restrictions will play out largely a matter of speculation, that I put other permissions also in the class of probably important rather than unambiguously required.

Each of these merit much more experimentation and critique, but while any progress on the first two will inevitably be controversial, progress on the third ought be celebrated and demanded. (For completeness sake, progressive changes in social policy must also be celebrated and demanded, but out of scope for this post.) I see few excuses for new licenses and dedications to not aggressively grant every permission that might be possible or needed, nor for new projects to use instruments that are not so aggressive (with the gigantic constraints that use of existing works and the non-existence of perfect instruments impose), nor for communities that vet instruments to give a stamp of approval to such instruments — indeed if politics and path dependencies were not an issues, such communities ought to push non-aggressive instruments to some kind of legacy status.

In this context I am happy with the outcome of the submission of CC0 to the Open Source Initiative for approval: due to not only lack of, but explicit exclusion of patent permissions, Creative Commons has withdrawn the submission. Richard Fontana’s and Bruce Perens’ contributions to the thread are instructive.

I still think that CC0 is the best thing Creative Commons has ever done — indeed I think that largely because of the above considerations; I don’t know of an instrument that makes as thorough attempt to grant permission around all copyright, related, and neighboring restrictions (patents aren’t in any of those classes) — and remain very happy that the Free Software Foundation considers CC0 to be GPL-compatible (I put GPL-incompatibility in a class of avoidable failure separate from but not wholly unlike not granting all permissions that may be possible, unless one is experimenting with some really novel copyleft regulation).

From the OSI submission thread, I also highly recommend Carl Boettiger’s plea for a public domain instrument appropriate for heterogeneous (code/data/other) products. It will (and ought to) take Creative Commons a long time to vet any potential new version of CC0, but fortunately as I’ve pointed out before, there is plenty of room for experimentation with public domain mechanisms, especially around branding (as incompatibility is less of an issue; compare with copyleft (although if one made explicit compatibility a requirement, there is plenty of potentially beneficial exploration to be done there, too)). An example of such that attempts to include a patent waiver is the Ampify Unlicense (background post).

I hope that the CC0/OSI discussion prompts a race to the bottom for public domain instruments, as new ones attempt to carve out every possible permission. This also ought beneficially affect future permissive and copyleft licenses, which also ought grant every permission possible, whatever conditions they layer on top. Note that adding one such permission — around sui generis database restrictions, is probably the most pressing reason for Creative Commons to have started working on version 4.0 of its licenses. I also hope that the discussion leads to increased collaboration and knowledge sharing (at the very least) across domains in which public licenses are used, taking into account Boettiger’s plea and the realities that such licenses are very often used across several domains (a major point of my recent FOSDEM talk, see especially slides 8-11) and that knowledge concerning commons governance is very thin in every domain.

But keep in mind that most of this post concerns very small potential gains relative to merely granting copyright permission (assuming no non-free conditions are present) and even those are quite a niche subject.☻