Open source doesn’t just mean access to the source code. The distribution terms of an open-source program must comply with the following criteria:
1. Free Redistribution
The license may not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several different sources. The license may not require a royalty or other fee for such sale.
2. Source Code
The program must include source code, and must allow distribution in source code as well as compiled form. Where some form of a product is not distributed with source code, there must be a well-publicized means of downloading the source code, without charge, via the Internet. The source code must be the preferred form in which a programmer would modify the program. Deliberately obfuscated source code is not allowed. Intermediate forms such as the output of a preprocessor or translator are not allowed.
3. Derived Works
The license must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software.
4. Integrity of The Author’s Source Code.
The license may restrict source-code from being distributed in modified form only if the license allows the distribution of “patch files” with the source code for the purpose of modifying the program at build time. The license must explicitly permit distribution of software built from modified source code. The license may require derived works to carry a different name or version number from the original software.
5. No Discrimination Against Persons or Groups.
The license must not discriminate against any person or group of persons.
6. No Discrimination Against Fields of Endeavor.
The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research.
7. Distribution of License.
The rights attached to the program must apply to all to whom the program is redistributed without the need for execution of an additional license by those parties.
8. License Must Not Be Specific to a Product.
The rights attached to the program must not depend on the program’s being part of a particular software distribution. If the program is extracted from that distribution and used or distributed within the terms of the program’s license, all parties to whom the program is redistributed should have the same rights as those that are granted in conjunction with the original software distribution.
9. License Must Not Contaminate Other Software.
The license must not place restrictions on other software that is distributed along with the licensed software. For example, the license must not insist that all other programs distributed on the same medium must be open-source software.
10. Conforming Licenses and Certification.
Any software that uses licenses that are certified conformant to the Open Source Definition may use the Open Source trademark, as may source code explicitly placed in the public domain. No other license or software is certified to use the Open Source trademark.
(The following information is not part of the Open Source Definition, and it may change from time to time.)
The GNU GPL, the LGPL, the BSD license, the X Consortium license, the Artistic, the MPL and the QPL are examples of licenses that we consider conformant to the Open Source Definition.
To have a license reviewed for certification, write [email protected]. We strongly encourage use of already-certified licenses from the above list, since this allows use of the Open Source mark without the need for review. Please report misuse of the Open Source mark to [email protected].
Change history:
1.0 — identical to DFSG, except for addition of MPL and QPL to clause 10.
1.1 — added LGPL to clause 10.
1.2 — added public-domain to clause 10.
1.3 — retitled clause 10 and split off the license list, adding material on procedures.
1.4 — Now explicit about source code requirement for PD software.
Bruce Perens wrote the first draft of this document as `The Debian Free Software Guidelines’, and refined it using the comments of the Debian developers in a month-long e-mail conference in June, 1997. He removed the Debian-specific references from the document to create the `Open Source Definition’.
Version 1.4, last modified, ????-??-??