Creative Commons licenses help creators (and users) opt for reasonable copyright by offering (and using) creative works under “some rights reserved” terms, expanding the commons where the default is “all rights reserved”.
We also offer tools to mark works that are in the public domain — and are working on a major upgrade of those tools — with a goal of making public domain works more available and more usable, effectively expanding the “no rights reserved” portion of the commons.
However, there’s nothing CC tools can do to protect against the stunting of the public domain through fiat, such as the retroactive extension of copyright terms. This is why many friends of CC are involved in efforts like Sound Copyright, a petition to the European Union to stop the retroactive extension of copyright in sound recordings from 50 years to 95 years.
Read about why retroactive copyright extension is bad policy — it offers miniscule incentive for the creation of new works while imposing large costs on the preservation and use of existing works. As a beneficial side effect, you’ll better understand the milieu from which Creative Commons arises and why the voluntary adoption of reasonable copyright through tools like ours are crucial to ensuring the existence of a viable commons — an open, participatory culture — for future generations.