- Ownership: You own the code you write, or you gained ownership either through employment contract or CLA.
- License: A software license defines the legal terms under which the software and its source code may be used. A code owner can choose the license for his software and change it at any time.
- License Types:
- Open source licenses grant users the four essential freedoms: the freedom to use the code for any purpose, the freedom to study it, the freedom to modify it, and the freedom to redistribute it. Proprietary licenses violate at least one of the four freedoms.
- Proprietary software has two major risks: black-boxing and vendor lock-in.
- License Examples
- Proprietary
- All rights reserved license, is usually applied to closed source code. It prohibits each use not authorized by the owner.
- Cloud: Is proprietary but rather close to open source. Prevents cloud providers from commercially using their product in order to gerneate revenue. Also integrates a open source publishing delay. BSL has a 4 year delay while the FSL only has 2 years.
- Open Source
- Permissive: Allow reuse in other projects, even proprietary products, with no big strings attached like MIT, or even a public domain license, with no strings attached at all like the 0BSD license.
- Copyleft: All derivative works must have the same license to remain open source. Source code must be made available to all users of the software.
- Proprietary
- Revenue: Proprietary software is less attractive to users because of its risks, but easier to make money with. With open source, the situation is reversed.
- Revenue Models
- Proprietary: All code is proprietary. User must unlock the software through a purchased product key.
- Pure Open Source: Realized either by paying directly for open source development or by providing services around an open source product.
- Open Core: Combines the strengths of proprietary and open source models.
- Proprietary Edition Model: An open source community edition and a proprietary closed source enterprise edition.
- Proprietary Extension Model: A pure open source platform on which proprietary extensions can be loaded.
- Cloud Licenses can be an additional way to generate revenue from the community edition while staying committed to open source.
License Overview
This is a brief summary of how the license of a 3rd party software project affects my rights to reuse it in your own project, and the right to relicense the 3rd party code. The right to relicense is actually the exception, and only possible for code that is public domain equivalent code or code that you own.
