There's more information here: http://www.mongodb.org/display/DOCS/Licensing http://www.mongodb.org/display/DOCS/Licensing The way I understand it, is that the

There's more information here: http://www.mongodb.org/display/DOCS/Licensing http://www.mongodb.org/display/DOCS/Licensing The way I understand it, is that they use AGPL to prevent people from running their own customized mongodb daemons without publishing the patches. This solves the "problem" of web services customizing code and not publishing patches because they're technically not distributing any code. Note that this doesn't apply to the client drivers, so you can still safely link the drivers into your code and/or modify these drivers.