I'm quite confused with MongoDB's licensing model. MongoDB at it'sits core is an open-source project, licensed under the SSPL which is a littlesmall modification of the AGPLv3 license, then. Then how does it release enterprise versions of it'sits software with advanced features with an entirely different proprietary license which still uses AGPL code? Why doesn't MongoDB have to release it'sits modifications?
Does MongoDB being the copyright holder give it these rights? Then what about the contributions made to MongoDB by the folks in the OSS community? How does MongoDB incorporate these changes to it'sits proprietary solutions?
(I am an absolute novice in open-source, so please be liberal!)