Not open source. Not closed source. The Fair Source License allows everyone to see the source code and makes the software free to use for a limited number of users in your organization. It offers some of the benefits of open source while preserving the ability to charge for the software.
Any individual user can view, download, execute, and modify the code free of charge. Up to a certain number of users from an organization can use the code for free, too. After an organization hits that user limit, it will start paying a licensing fee determined by the software publisher.
The Fair Source License can be applied to software applications and their source code. It is not currently suitable for library or plugin code.