Sequoia PGP is owned by the p≡p foundation and licensed under the terms of the LGPLv2+.
To finance its mission, privacy by default, the p≡p foundation allows third parties (currently only p≡p security) to relicense its software. Consistent with the rules of a foundation, the money collected by the foundation in this manner is fully reinvested in the foundation's mission, which includes further development of Sequoia PGP.
To do this, the p≡p foundation needs permission from all contributors to relicense their changes. In return, the p≡p foundation guarantees that all releases of Sequoia PGP (and any other software it owns) will also be released under a GNU-approved license. That is, even if Foo Corp is granted a license to use Sequoia PGP in a proprietary product, the exact code that Foo Corp uses will also be licensed under a GNU-approved license.
If you want to contribute to Sequoia PGP, and you agree to the above, please sign the p≡p foundation's CLA. This is an electronic assignment; no paper work is required. You'll need to provide a valid email address. After clicking on a link to verify your email address, you'll receive a second email, which contains the contract between you and the p≡p foundation. Be sure to keep it for future reference. The maintainers of Sequoia PGP will also receive a notification. At that point, we can merge patches from you into Sequoia PGP.
Please direct questions regarding the CLA to contribution@pep.foundation.