OurBigBook DocsWe require all contributions to give the OurBigBook Project non-exclusive rights to their contributions.
This means that contributors retain their copyright, and may reuse their part of the code as they see fit under additional licenses beyond AGPL, but so can the OurBigBook Project.
The AGPL can of course cannot never be revoked once it has been applied. This only means that copyright owners may at any point also release their IP under another license.
The main rationale for this right now is to allow the OurBigBook Project the flexibility to one day allow someone to pay for a license that doesn't require releasing their source code under the AGPL without having to get all contributors ever to agree. This scenario is very unlikely to ever happen.
The OurBigBook Projects's commitment is and always will be to provide free education for all, and we have no plans to ever make anything closed source. But if it ever happens that we absolutely run out of the only way to achieve the goals of free education is to make concessions and allow enterprise users to pay for using the site for their purposes, which is not the case at this point, we would like to keep that door open.
Such CLA would also make it easier for the OurBigBook Project to be able to fight in court to enforce the AGPL's term's should that need ever arise.