CLAs can be used to enable vendors to easily pursue legal resolution in the case of copyright disputes,[1] or to relicense products to which contributions have been received from third parties.
The purpose of a CLA is to ensure that the guardian of a project's outputs has the necessary ownership or grants of rights over all contributions to allow them to distribute under the chosen license, often by granting an irrevocable license to allow the project maintainer to use the contribution; if copyright is actually transferred, the agreement is more normally known as a Copyright Transfer Agreement.
[...] Our license change is aimed at preventing companies from taking our Elasticsearch and Kibana products and providing them directly as a service without collaborating with us.
We’ve tried every avenue available including going through the courts, but with AWS’s ongoing behavior, we have decided to change our license so that we can focus on building products and innovating rather than litigating [...] [7] Drew DeVault, a lead developer with a number of open source projects such as Sway, regards this move as a loophole.
This is the loophole which Elastic exploited when they decided that Elasticsearch would no longer be open source [...][8]Project Harmony was established by Canonical in 2010 to optionally avoid the problems discussed above.