Knowledge Tree
The Open Source Definition
Also known as: The Open Source Definition, Open Source Definition, OSD, The Open Source Definition (Annotated)
Facts (94)
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The Open Source Definition - Wikipedia en.wikipedia.org 30 facts
claimOpen Source Software is defined as software released under a license that conforms to the Open Source Definition (OSD), as articulated by the Open Source Initiative.
claimThe Open Source Definition is the most widely used definition for open-source software and serves as a standard for determining whether a project qualifies as open source.
procedureThe Open Source Initiative board votes on proposals of software licenses to certify that they are compliant with the Open Source Definition and maintains a list of compliant licenses on its website.
claimThe Open Source Definition requires that software licenses permit free redistribution of the software.
accountRichard Stallman promoted the Free Software Definition to differentiate free software from open source after the Debian Free Software Guidelines (DFSG) became the Open Source Definition.
claimThe Open Source Definition requires that software licenses must not mandate the distribution of source modifications to anyone other than the recipient of the modified binary, as such requirements could endanger users.
claimThe Open Source Definition prohibits discrimination between users and between uses, including commercial use.
claimThe Open Source Definition has been adapted into the Open Knowledge Foundation's Open Definition for open knowledge and into various open hardware definitions.
claimThe Open Source Definition allows licenses to require that the original software be distributed intact, provided that modifications can be distributed as patches without restriction.
claimThe Open Source Definition requires that the license must cover all the code, not just a particular product or distribution.
claimThe Open Source Definition requires that everyone who receives a copy of the program is granted all the open-source rights.
claimThe Open Source Definition covers both copyleft licenses, where redistribution and derivative works must be released under a free license, and permissive licenses, where derivative works can be released under any license.
perspectiveThe Open Source Definition is effectively identical to the definition of free software, but it is motivated by more pragmatic and business-friendly considerations.
procedureThe Open Source Initiative (OSI) uses the criteria in the Open Source Definition to approve licenses as compatible and maintains a list of compliant licenses.
perspectiveThe Open Source Definition is part of the open source movement rather than the free software movement and seeks to promote the availability of open-source software for anyone, including makers of proprietary software.
claimThe Open Source Definition prohibits restrictions on other software distributed at the same time as the open-source software.
claimThe Open Source Definition requires technological neutrality, meaning a license cannot restrict use to any particular technology, such as requiring a user to click a box to agree to terms if that prevents distribution as a paper copy.
claimOpen Source Software (OSS) is released under a license that complies with the Open Source Definition as articulated by the Open Source Initiative (OSI).
claimThe Open Source Definition requires that derivative works must be allowed and able to be redistributed under the same licensing terms as the original open-source product.
claimThe Open Source Initiative (OSI) adopted a modified version of the Debian Free Software Guidelines as the Open Source Definition.
claimThe Open Source Definition requires that ten specific criteria be met for software to be considered open-source, and merely providing access to source code is insufficient.
claimIt has been claimed that the Open Source Definition was created by re-titling the exact text of the Debian Free Software Guidelines (DFSG).
claimThe Open Source Hardware Statement of Principles is adapted from the Open Source Definition.
claimThe Open Source Definition is a policy document published by the Open Source Initiative in 1998 that serves as the predominant standard for open-source software.
claimThe Open Source Initiative (OSI) adopted a closed organizational model rather than a membership-driven one to facilitate drafting the Open Source Definition and collaborating with a diverse range of stakeholders.
claimThe Open Source Definition is available under a Creative Commons (CC BY 4.0) license.
claimThe Open Knowledge Foundation's Open Definition is substantially derivative of the Open Source Definition.
claimThe Open Source Definition requires that source code must be accessible and the license must permit redistribution in the form of source code rather than object code, as access to source code is necessary to modify the software.
claimThe Open Source Definition and the official definitions of free software by the Free Software Foundation (FSF) essentially cover the same set of software licenses.
claimThe Open Source Definition does not address warranty disclaimers, nor does it specify a governance structure for open-source projects.
The Open Source Definition (Annotated) opensource.org 13 facts
claimThe Open Source Definition requires that rights attached to a program must apply to all parties to whom the program is redistributed without requiring the execution of an additional license, which prevents the use of non-disclosure agreements to close software.
claimIf a product is distributed without source code, the Open Source Definition requires a well-publicized method for obtaining the source code for no more than a reasonable reproduction cost, preferably via free Internet download.
claimThe Open Source Definition establishes that open source software is defined by more than just access to source code; its distribution terms must comply with specific criteria regarding redistribution, source code access, derived works, and integrity.
measurementThe Open Source Definition (Annotated) is version 1.9, which was last modified on March 22, 2007.
claimThe GNU General Public License (GPL) versions 2 and 3 are conformant with the Open Source Definition requirement regarding non-restriction of other software, as software linked with GPLed libraries only inherits the GPL if it forms a single work.
claimThe Open Source Definition requires that licenses explicitly permit the distribution of software built from modified source code, though they may require derived works to carry a different name or version number than the original software.
claimThe Open Source Definition requires that software programs include source code and allow distribution in both source code and compiled forms.
claimThe Open Source Definition requires that a license must not place restrictions on other software distributed along with the licensed software, such as mandating that all other programs on the same medium must be open source.
claimThe Open Source Definition requires that licenses must be technology-neutral, meaning no provision can be predicated on any individual technology or style of interface, which specifically targets licenses that require explicit gestures of assent to establish a contract.
claimThe Open Source Definition prohibits licenses from requiring a royalty or other fee for the sale of software as part of an aggregate distribution.
claimThe Open Source Definition requires that software licenses allow free redistribution, meaning the license cannot restrict any party from selling or giving away the software as part of an aggregate software distribution containing programs from several different sources.
claimThe Open Source Definition mandates that source code must be provided in the preferred form for a programmer to modify the program, explicitly prohibiting deliberately obfuscated code or intermediate forms like preprocessor output.
claimThe Open Source Definition requires that licenses must not discriminate against any person or group of persons, ensuring that the maximum diversity of contributors is eligible to participate in the open source process.
The Open Source Definition opensource.org 11 facts
procedureThe Open Source Definition mandates that software licenses must not discriminate against any person or group of persons.
measurementThe Open Source Definition reached version 1.9 on March 22, 2007.
procedureThe Open Source Definition requires that the rights attached to a program must apply to all parties to whom the program is redistributed without requiring the execution of an additional license by those parties.
claimThe Open Source Definition was originally derived from the Debian Free Software Guidelines (DFSG).
procedureThe Open Source Definition mandates that software licenses must not restrict anyone from using the program in any specific field of endeavor, such as business or genetic research.
procedureThe Open Source Definition requires that software must include source code and allow distribution in both source code and compiled forms. If source code is not distributed with the product, there must be a well-publicized, low-cost means of obtaining it, preferably via free internet download. The source code must be the preferred form for modification, and deliberately obfuscated code or intermediate forms like preprocessor output are prohibited.
claimThe Open Source Definition requires that an Open Source Software license must allow modifications and derived works, and must allow those modifications and derived works to be distributed under the same terms as the license of the original software.
procedureThe Open Source Definition requires that the rights attached to a program must not depend on the program being part of a particular software distribution. If a program is extracted from a distribution and used or distributed under its license terms, all parties to whom it is redistributed must receive the same rights granted in the original distribution.
claimThe Open Source Definition asserts that open source software distribution terms must comply with ten specific criteria, extending beyond mere access to source code.
procedureThe Open Source Definition allows licenses to restrict the distribution of modified source code only if the license permits the distribution of 'patch files' for build-time modification. Licenses must explicitly permit the distribution of software built from modified source code and may require derived works to carry a different name or version number than the original software.
referenceThe 'Annotated OSD' is a historical document published in the early 2000s that provides annotations for the Open Source Definition.
Free and open-source software - Wikipedia en.wikipedia.org 7 facts
referenceBruce Perens defined 'The Open Source Definition' in the 1999 book 'Open Sources: Voices from the Open Source Revolution'.
claimThe two predominant strains of FOSS (Free and Open-Source Software) licenses are those that comply with the Open Source Initiative's 'Open Source Definition' and those that comply with the Free Software Foundation's 'Free Software Definition'.
claimThe Open Source Initiative maintains 'The Open Source Definition', which was last updated or referenced on July 7, 2006.
claimThe Open Source Initiative (OSI) uses 'The Open Source Definition' to determine whether a software license qualifies for the organization's insignia for open-source software.
claimThe Open Source Definition was based on the Debian Free Software Guidelines, which were written and adapted primarily by Bruce Perens.
claimThe rights guaranteed by Free and open-source software (FOSS) originate from the 'Four Essential Freedoms' of The Free Software Definition and the criteria of The Open Source Definition.
claimBruce Perens published 'The Open Source Definition' on March 29, 1999, which was later included in the book 'Open Sources: Voices from the Open Source Revolution'.
What is open source software? oss-watch.ac.uk May 1, 2005 4 facts
claimThe Open Source Definition, maintained by the Open Source Initiative (OSI), consists of 10 criteria that a licence must meet to be considered open source.
claimBoth the GNU General Public License (GPL) and the MIT licence meet the criteria of the Open Source Definition, despite having different lengths and intents.
claimThe Open Source Definition does not define the open development methodology, as it concerns itself only with the requirements of a licence designed to protect the way of developing software.
claimThe most important criteria of the Open Source Definition include the free redistribution of software, access to the source code, and the permission to allow modifications to the software and derived works that may be distributed under the same licensing conditions.
Open-source license - Wikipedia en.wikipedia.org 4 facts
claimThe Open Source Initiative adopted the Debian Free Software Guidelines as the foundation for the Open Source Definition.
claimThe Free Software Foundation maintains the Free Software Definition, which serves as a rival set of criteria to the Open Source Definition.
claimThe Free Software Definition, the Open Source Definition, and the Debian Free Software Guidelines all require that recipients of covered software have the ability to use, modify, and redistribute the work.
claimOpen-source licenses grant the recipient the rights to use software, examine the source code, modify it, and distribute the modifications, as outlined in the Open Source Definition.
Open-source software - Wikipedia en.wikipedia.org 4 facts
claimAll Free and Open Source Software (FOSS) is considered 'source available' because the Open Source Definition requires source code accessibility, but not all 'source available' software is FOSS.
claimBruce Perens authored 'The Open Source Definition', which serves as a foundational document for the Open Source Initiative's definition of open source software.
claimSoftware is not classified as Free and Open Source Software (FOSS) if it fails to meet the Open Source Definition requirements, such as permitting modification or redistribution, even if the source code is available to users.
referenceThe Open Source Initiative maintains 'The Open Source Definition (Annotated)', which serves as a foundational document for defining open source software.
What is OSS? - CircleCI circleci.com Jun 10, 2024 3 facts
referenceThe Open Source Initiative introduced the Open Source Definition (OSD) in 1998, which includes 10 characteristics that define what constitutes open source software.
claimSoftware that does not meet Open Source Definition (OSD) standards is not considered Open Source Software (OSS).
claimThe Open Source Definition (OSD) prohibits discrimination against any individuals, groups, or fields of use, mandates consistent licensing for all users, and requires that licenses remain neutral to technology.
The Complete Guide to Open Source Licenses - FOSSA fossa.com 3 facts
referenceThe Open Source Definition, maintained by the Open Source Initiative, requires that a license must allow free redistribution, ensure source code availability, permit the creation of derivative works, maintain the integrity of the author's source code, prohibit discrimination against persons or groups, prohibit discrimination against fields of endeavor, require distribution of the license, not be specific to a product, not restrict other software, and be technology-neutral.
perspectiveSome proponents argue that the Open Source Definition should evolve to accommodate ethical restrictions in software licenses.
claimEmerging software licenses are causing a debate regarding the Open Source Definition (OSD).
What is Open Source Software (OSS)? - Harness harness.io Dec 17, 2025 2 facts
claimThe Open Source Initiative maintains a list of open source licenses that comply with the Open Source Definition to provide a reference for developers and users to ensure legal compliance.
claimThe Open Source Definition, maintained by the Open Source Initiative, establishes criteria for software to be considered open source, including principles of free redistribution, access to source code, derived works, non-discrimination, and the absence of restrictive license terms.
Open Source Software, Public Policy, and the Stakes of Getting It Right opensource.org Jan 26, 2026 2 facts
claimThe Open Source Initiative (OSI) is a nonprofit organization that has served as the steward of the Open Source Definition since the late 1990s.
claimThe Open Source Initiative (OSI) maintains an active license review committee that evaluates software license submissions against the Open Source Definition to ensure software remains genuinely open.
Seven observations and research questions about Open Design ... cambridge.org Oct 19, 2021 2 facts
referenceThe Open Source Initiative (2007) defines core principles for the Open Source Definition, including nondiscrimination against persons or groups and nondiscrimination against fields of endeavor.
claimNeither Huizingh’s nor Balka’s definitions of open source innovation reference the Open Source Definition or the Open Source Hardware definitions.
Open-source hardware - Wikipedia, the free encyclopedia smoothieware.github.io Apr 15, 2016 2 facts
accountBruce Perens, creator of the Open Source Definition and co-founder of the Open Source Initiative, started the first hardware-focused open source activities around 1997.
claimOpenhardware.org, led by Bruce Perens, promoted and identified practices that met the combined requirements of the Open Source Hardware Definition, the Open Source Definition, and the Four Freedoms of the Free Software Foundation.
What Is Open Source Software Licensing? - Coursera coursera.org Dec 9, 2025 1 fact
referenceThe Open Source Initiative maintains 'The Open Source Definition', which is available at https://opensource.org/osd.
What Is Open Source Software? - IBM ibm.com 1 fact
claimThe Open Source Initiative (OCI) was created to advocate for open source software, establish industry ground rules through the open source definition, and host compliant open source licenses.
Open source software best practices and supply chain risk ... - GOV.UK gov.uk Mar 3, 2025 1 fact
referenceThe Open Source Definition (2024) states that a key advantage of open-source software is the explicit permission granted to duplicate and independently alter the source code of an open-source project as desired.
Defining open hardware - LWN.net lwn.net Oct 18, 2023 1 fact
claimThe Open Source Hardware Association (OSHWA) definition of open-source hardware is made explicit in 12 criteria that are not unlike the ten criteria of the Open Source Definition.
What's the definition of "Open Source Hardware?" - WIRED wired.com Jul 16, 2010 1 fact
claimThe Open Source Hardware (OSHW) Draft Definition version 0.3 is based on the Open Source Definition for Open Source Software and the draft OSHW definition 0.2.
Unknown source 1 fact
claimOpen source licenses are defined as licenses that comply with the Open Source Definition, which allows software to be freely used, modified, and shared.
Open Source Hardware Definition | OSHWA oshwa.org 1 fact
referenceThe Open Source Hardware (OSHW) Definition 1.0 is based on the Open Source Definition for Open Source Software, which was created by Bruce Perens and the Debian developers as the Debian Free Software Guidelines.