What is the MIT License?
The MIT License is an agreement commonly used by software developers when they release Free and Open Source software. It is more precisely named the Expat License, to disambiguate it from similar licenses.
What does the MIT License mean?
When an author makes software available under the MIT License, they are granting you permission to use, share and modify the software at no additional cost, and for you to optionally grant the same right to others, subject to two conditions:
- You agree not to blame the author if the software doesn't work properly.
- The author will still own the copyright to their work, so you can't remove the license. If you modify the software, you should be clear about any changes you have made, and what license you are distributing those changes under.
Sometimes only part of a software package is MIT Licensed. For example, the software may include graphics under a different license, or may come with certain non-free additions. The author of the software will usually make the scope of the license clear.
Can I use MIT-licensed code commercially?
Yes. There are no restrictions on commercial use.
Can I use MIT-licensed code in closed-source software?
Yes, however the copyright notice and permission notice must be included in the documentation or EULA of your Software.
For example: "This software uses <library name> - see library-license.txt".
How do I display the MIT License if my project has no documentation or “about” feature?
Contact the author. If the author agrees, a notice on your product website may suffice as documentation.
Can I redistribute MIT-licensed code under another license?
Yes. You cannot "re-license" MIT-licensed code, and the MIT-licensed code will remain under the MIT License, but you can redistribute it as part of another project under any license you wish. You should make it clear that any changes that you make to the MIT-licensed code are released under your new license. The MIT License text & copyright notice must still be included with any unmodified MIT-licensed code.
Can I use MIT-licensed code in my GPL-licensed project?
Can I use GPL-licensed code in my MIT-licensed project?
No. The project as a whole must conform to the terms of the GPL license and must be distributed under the terms of that license. Therefore such a project as a whole must be distributed as GPL, but can still contain MIT-licensed software.
If I use MIT-licensed software server-side, do I have to display the copyright notice or disclaimer?
Having MIT-licensed software work server-side (e.g. as a PHP script) to produce a HTML page is not redistributing the software, unless the program includes itself in its output. Therefore you are not giving the user any sort of license to the original software, nor are you required to do so. This even applies to GPL-licensed software.
However, if you are in any way sharing your server-side software with another party, the terms of the license obviously apply in relation to that distribution. The exception to this would be providing the software to a sub-contractor (e.g. a website hosting company) where you do not grant them any license to redistribute or use the software except as directed by yourself. This also applies to the GPL.
How do I use the MIT License?
- When you release source code, put a copy of the MIT License text at the top of each source file as a comment.
- When you release a software package, include a copy of the MIT License in the root directory of the package. Name the file ‘COPYING’ or ‘LICENSE’.
- Display the MIT License as part of your software's End User License Agreement (EULA).
- Display the MIT License in any documentation.
When you display the MIT License, you should also display any copyright information and, if appropriate, make it clear what the license applies to.
What is the MIT License text?
Copyright © <years> <copyright holder>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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 AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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