Choose and use the right license for your software tool

Whether you are a software developer wishing to distribute your tool, or a user/programmer in need to use and/or modify a tool, you are confronted to licensing. Software licenses govern the use or redistribution of a software under specific laws. Two common categories for software under copyright law (which grants the licensee specific rights) are proprietary software and free and open source software (FOSS). The main difference between proprietary and FOSS license is the granting of rights to modify and re-use a software by a customer: FOSS software licenses both rights to the customer, while proprietary software does not license these rights (Wikipedia).


Software licenses on OMICtools


Following the general tendency to develop more open-source software, more than 90% of software licenses in the OMICtools database are free and open-source. However, a lot of different licenses have been developed, with their own subtleties (Table 1).


GNU General Public License version 3.0 2551 32,5%
GNU General Public License version 2.0 2020 25,8%
MIT License 838 10,7%
Apache License version 2.0 421 5,4%
BSD 3-clause New or Revised Licence 388 5,0%
GNU Lesser General Public License version 3.0 352 4,5%
Artistic License version 2.0 341 4,4%
Commercial 270 3,4%
BSD 2-clause, Simplified License 175 2,2%
Other 166 2,1%
GNU Affero General Public License version 3 112 1,4%
CeCILL version 2.1 63 0,8%
GNU Lesser General Public License version 2.1 49 0,6%
Academic Free License version 3.0 45 0,6%
Mozilla Public License version 2.0 17 0,2%
Eclipse Public License version 1.0 10 0,1%
ISC License 9 0,1%
Common Public License Version 1.0 7 0,1%
Boost Software License 1.0 3 0,0%
The Unlicense 1 0,0%
Total 7838  100%

Table 1: Software licenses registered in OMICtools.


Here is a quick summary of the most used software licenses on OMICtools:


  • GNU General Public License (all versions): The GNU GPL is the most used license in OMICtools, and one of the most used worldwide. It guarantees users freedom to run, study, share and modify the software. The GPL is a copyleft license, which means that derivative work can only be distributed under the same license terms.


  • MIT license: The MIT license is a permissive free software license originally developed at the Massachusetts Institute of Technology (MIT). It is the most popular software license on GitHub, on the second most popular in OMICtools. As a permissive license, it puts very limited restriction on reuse. Contrary to the GNU GPL, it has no copyleft, which means that when the software is being redistributed (either modified or unmodified), the redistributor is not enforced to open the modified source code.


  • Apache License and BSD Licenses: The Apache and BSD family of license are permissive free software licenses that impose minimal restrictions on the use and redistribution of licensed software. These licenses are not copyleft.


Comparative table


To further help you choose among all available licenses, here are some definitions you might be confronted to while browsing our comparative table (Table 2):

  • Linking- linking of the licensed code with code licensed under a different license (e.g. when the code is provided as a library
  • Distribution- distribution of the code to third parties
  • Modification- modification of the code by a licensee
  • Patent grant- protection of licensees from patent claims made by code contributors regarding their contribution, and protection of contributors from patent claims made by licensees
  • Private use- whether modification to the code must be shared with the community or may be used privately (e.g. internal use by a corporation)
  • Sublicensing- whether modified code may be licensed under a different license (for example a copyright) or must retain the same license under which it was provided



Comparison of free and open source (Wikipedia)

Free Software license (Wikipedia)