# Specialty & Other Open Source Licenses Licenses with specific use cases or unique characteristics. --- ## Creative Commons Licenses Creative Commons licenses are primarily designed for **creative works** (documentation, images, datasets), NOT software code. For software, use a proper OSS license instead. ### CC BY 4.0 (Attribution) **SPDX Identifier:** `CC-BY-4.0` **Use Cases:** Documentation, images, datasets, educational materials **Notable Projects:** Wikipedia content, many documentation sites, OpenStreetMap data ``` Creative Commons Attribution 4.0 International You are free to: - Share — copy and redistribute the material in any medium or format - Adapt — remix, transform, and build upon the material for any purpose, even commercially Under the following terms: - Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits. [Full text: https://creativecommons.org/licenses/by/4.0/legalcode] ``` ### CC BY-SA 4.0 (Attribution-ShareAlike) **SPDX Identifier:** `CC-BY-SA-4.0` **Use Cases:** Wikipedia, wikis, collaborative documentation ``` Creative Commons Attribution-ShareAlike 4.0 International You are free to: - Share — copy and redistribute the material in any medium or format - Adapt — remix, transform, and build upon the material for any purpose, even commercially Under the following terms: - Attribution — You must give appropriate credit - ShareAlike — If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original [Full text: https://creativecommons.org/licenses/by-sa/4.0/legalcode] ``` ### CC BY-NC 4.0 (Attribution-NonCommercial) **SPDX Identifier:** `CC-BY-NC-4.0` **Note:** NOT an open source license (restricts commercial use) ``` Creative Commons Attribution-NonCommercial 4.0 International You are free to: - Share — copy and redistribute the material in any medium or format - Adapt — remix, transform, and build upon the material Under the following terms: - Attribution — You must give appropriate credit - NonCommercial — You may not use the material for commercial purposes [Full text: https://creativecommons.org/licenses/by-nc/4.0/legalcode] ``` **Warning:** CC-BY-NC is NOT OSI-approved and NOT considered open source because it restricts commercial use. --- ## WTFPL (Do What The F*ck You Want To Public License) **SPDX Identifier:** `WTFPL` **Notable Projects:** Various small projects, memes ### Canonical Text ``` DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE Version 2, December 2004 Copyright (C) 2004 Sam Hocevar Everyone is permitted to copy and distribute verbatim or modified copies of this license document, and changing it is allowed as long as the name is changed. DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 0. You just DO WHAT THE FUCK YOU WANT TO. ``` ### Characteristics - Essentially public domain - Humorous/informal - May have enforceability concerns in professional contexts - Not recommended for serious projects --- ## Artistic License 2.0 **SPDX Identifier:** `Artistic-2.0` **Notable Projects:** Perl, CPAN modules ### Key Characteristics - Permissive with conditions - Distinguishes between "Standard Version" and modifications - Requires renaming modified versions or clearly marking changes - Used primarily in Perl ecosystem --- ## Boost Software License 1.0 (BSL-1.0) **SPDX Identifier:** `BSL-1.0` **Notable Projects:** Boost C++ Libraries ### Canonical Text ``` Boost Software License - Version 1.0 - August 17th, 2003 Permission is hereby granted, free of charge, to any person or organization obtaining a copy of the software and accompanying documentation covered by this license (the "Software") to use, reproduce, display, distribute, execute, and transmit the Software, and to prepare derivative works of the Software, and to permit third-parties to whom the Software is furnished to do so, all subject to the following: The copyright notices in the Software and this entire statement, including the above license grant, this restriction and the following disclaimer, must be included in all copies of the Software, in whole or in part, and all derivative works of the Software, unless such copies or derivative works are solely in the form of machine-executable object code generated by a source language processor. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ``` ### Key Characteristics - Very permissive - No attribution required for binary distributions - Simple and short - Popular in C++ community --- ## zlib License **SPDX Identifier:** `Zlib` **Notable Projects:** zlib, libpng, many games ### Canonical Text ``` zlib License Copyright (c) This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions: 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 3. This notice may not be removed or altered from any source distribution. ``` ### Key Characteristics - Very permissive - Must not misrepresent origin - Modified versions must be marked - Acknowledgment appreciated but not required - Popular in game development --- ## PostgreSQL License **SPDX Identifier:** `PostgreSQL` **Notable Projects:** PostgreSQL ### Canonical Text ``` PostgreSQL License Copyright (c) [year], [fullname] Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies. IN NO EVENT SHALL [COPYRIGHT HOLDER] BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF [COPYRIGHT HOLDER] HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. [COPYRIGHT HOLDER] SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND [COPYRIGHT HOLDER] HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. ``` ### Key Characteristics - BSD-like permissive license - Very liberal - Used specifically by PostgreSQL project --- ## Dual Licensing Some projects use dual licensing strategies: ### Common Patterns 1. **GPL + Commercial**: Project is GPL for open source use, commercial license available for proprietary use - Examples: MySQL, Qt, MongoDB (historical) 2. **MIT/Apache + Patent**: Permissive license with separate patent grant - Example: React (MIT + Facebook patent grant, later changed to MIT only) 3. **LGPL + Commercial**: Library is LGPL, commercial license for static linking - Example: Qt ### How to Indicate Dual Licensing ``` This project is dual-licensed under [License A] and [License B]. You may choose either license to govern your use of this software. SPDX-License-Identifier: MIT OR Apache-2.0 ``` --- ## Non-OSS "Source Available" Licenses **Warning:** These are NOT open source licenses per OSI definition. ### Server Side Public License (SSPL) **Used by:** MongoDB (current), Elastic (historical) - Similar to AGPL but more restrictive - Requires releasing entire stack as SSPL if offering as a service - NOT OSI-approved ### Business Source License (BSL / BUSL) **Used by:** MariaDB, HashiCorp (Terraform, Vault), Cockroach Labs - Time-delayed open source - Restricts production use initially - Converts to open source after specified period - NOT OSI-approved ### Elastic License 2.0 (ELv2) **Used by:** Elasticsearch, Kibana - Prohibits providing as a managed service - NOT OSI-approved **These licenses are mentioned for awareness only. They are not recommended for true open source projects.**