View source for ISC license

{{Short description|Permissive free software license}}
{{Use dmy dates|date=June 2016}}
{{Use American English|date=March 2021}}
{{ Infobox software license
| name            = ISC license
| author          = <!-- An author is always a person. Something cleverer than "Internet Systems Consortium", please! -->
| copyright       = [[Internet Systems Consortium]]
| OSI approved    = Yes<ref name="osi-licenses">{{Cite web |url=https://opensource.org/licenses/alphabetical |title=Licenses by Name |date=n.d. |website=[[Open Source Initiative]] |access-date=2017-07-20 |archive-url=https://web.archive.org/web/20170720141629/https://opensource.org/licenses/alphabetical |url-status=live |archive-date=2017-07-20 |quote=...&nbsp;The following licenses have been approved by the OSI.&nbsp;...{{Bulleted list|...|ISC License (ISC)|...}}}}</ref>
| Debian approved = Yes<ref name="dfsg-licenses">{{Cite web |url=https://www.debian.org/legal/licenses/ |title=License information |date=1997–2017 |publication-date=2017-07-12 |website=The [[Debian Project]] |publisher=[[Software in the Public Interest]] |access-date=2017-07-20 |archive-url=https://web.archive.org/web/20170720142826/https://www.debian.org/legal/licenses/ |url-status=live |archive-date=2017-07-20 |quote=...&nbsp;This page presents the opinion of some debian-legal contributors on how certain licenses follow the Debian Free Software Guidelines (DFSG).&nbsp;...&nbsp;Licenses currently found in Debian main include:{{Bulleted list|...|Expat/MIT-style licenses|...}}}}</ref>
| Free Software   = Yes<ref name="gnu-license-list-isc">{{Cite web |url=https://www.gnu.org/licenses/license-list.en.html |title=Various Licenses and Comments about Them |date=2014–2017 |publication-date=2017-04-04 |website=The [[GNU Project]] |publisher=[[Free Software Foundation]] |at=ISC License |access-date=2017-07-20 |archive-url=https://web.archive.org/web/20170720140022/https://www.gnu.org/licenses/license-list.en.html |url-status=live |archive-date=2017-07-20 |quote=...&nbsp;This is a lax, permissive free software license, and compatible with the GNU GPL.&nbsp;... This license is sometimes also known as the OpenBSD License, although there is one minor difference between the two licenses. The OpenBSD license was updated to remove the ambiguous term: "and/or".&nbsp;... At the time the ISC license was released, the use of "and/or" construct was a concern because it is similar language used in the license of Pine that the University of Washington later claimed prohibited people from distributing modified versions of the software.&nbsp;...}}</ref>
| GPL compatible  = Yes<ref name="gnu-license-list-isc"/>
| copyleft        = No<ref name="gnu-license-list-isc"/>
| linking         = Yes
| website         = {{Official URL}}
}}

The '''ISC license''' is a [[Permissive software license|permissive free software license]] published by the Internet Software Consortium, now called [[Internet Systems Consortium]] (ISC).  It is functionally equivalent to the [[BSD licenses#2-clause|simplified BSD]] and [[MIT License|MIT]] licenses, but without language deemed unnecessary following the [[Berne Convention]].{{refn|group=nb|"The ISC copyright is functionally equivalent to a two-term BSD copyright with language removed that is made unnecessary by the Berne convention."<ref name="openbsd-policy"/>}}{{refn|group=nb|"In OpenBSD we use an ISC-style copyright text [...] that is enough to satisfy every legal system on the planet which follows the Berne Convention."<ref name="theo2008"/>}}

Originally used for ISC software such as [[BIND]] and [[Dig (command)|dig]], it has become the preferred license for contributions to [[OpenBSD]]<ref name="openbsd-license-template"/> and the default license for [[npm (software)|npm]] packages.<ref name="npm-commit"/> The ISC license is also used for [[Linux kernel|Linux]] wireless drivers contributed by [[Qualcomm Atheros]],<ref>{{Cite web|url=http://linuxwireless.org/en/users/Drivers/Atheros/|title=en/users/Drivers/Atheros - Linux Wireless|website=linuxwireless.org|access-date=2017-07-15|archive-url=https://web.archive.org/web/20170621011348/http://linuxwireless.org/en/users/Drivers/Atheros/|archive-date=21 June 2017|url-status=dead}}</ref> as well as by the [[LV2]] plugin system.<ref>{{Cite web|url=https://gitlab.com/lv2/lv2/-/blob/master/COPYING|title=COPYING · master · LV2 / lv2 · GitLab|website=gitlab.com|access-date=2023-08-10}}</ref>

== License terms ==

{{quotation|<pre>
ISC License

Copyright <YEAR> <OWNER>

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.</pre>
|sign = |source = <ref>{{cite web |url = https://opensource.org/licenses/ISC |title = ISC License (ISC) |website = [[Open Source Initiative]] |language = en |access-date = 2017-07-15 }}</ref><ref>{{cite web |url = https://spdx.org/licenses/ISC.html |title = ISC License |website = [[Software Package Data Exchange]] |language = en |access-date = 2021-07-09 }}</ref>}}

When initially released, the license did not include the term "[[and/or]]", which was changed from "and" by ISC in 2007.<ref name="vixie">{{cite newsgroup |url=https://groups.google.com/forum/#!msg/comp.protocols.dns.bind/D8VLXloVfxc/4yweyAjRCecJ |title=BIND covered under which license and does it conatin any cryptographic content ? |newsgroup=comp.protocols.dns.bind |access-date=2017-07-15 |author=Vixie |author-link=Paul Vixie |first=Paul |date=20 July 2007 |via=[[Google Groups]]}}</ref> [[Paul Vixie]] stated on the BIND mailing list that the ISC license started using the term "and/or" to avoid controversy similar to the events surrounding the [[University of Washington]]'s refusal to allow distribution of the [[Pine (email client)|Pine]] email software.<ref name="vixie" /> Both versions of the license are compatible with the [[GNU General Public License|GNU GPL]].<ref name="gnu-license-list-isc" />

== OpenBSD license ==

The OpenBSD project began using the ISC license in 2003, before the 2007 addition of the term "and/or" to the license.<ref>{{cite web|url=https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/share/misc/license.template?rev=1.1&content-type=text/x-cvsweb-markup|title=src/share/misc/license.template - view - 1.1|date=2003-06-03}}</ref>
{{Quotation|text=<pre>
Copyright (c) YYYY YOUR-NAME-HERE <user@your.dom.ain>

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.</pre>
|sign=|source=<ref name="openbsd-license-template" />}}

[[Theo de Raadt]] of OpenBSD chose to retain the original wording, stating that he "disagrees with what ISC did" and is "not confident that their change is good" because "some country's legal systems might not understand 'and/or' in the way the old 'or' was used in the sentence".<ref name="theo2008"/>

== Reception ==
In 2015, ISC announced they would release their [[Kea (software)|Kea]] [[Dynamic Host Configuration Protocol|DHCP]] Software under the [[Mozilla Public License|Mozilla Public License 2.0]], stating, "There is no longer a good reason for ISC to have its own license, separate from everything else".<ref>{{Cite web|title=Kea to be released under Mozilla Public License 2.0 - Internet Systems Consortium|url=https://www.isc.org/blogs/kea-license-2-0/|access-date=2020-07-18|website=www.isc.org|date=8 December 2015 }}</ref> They also preferred a copyleft license, stating, "If a company uses our software but improves it, we really want those improvements to go back into the master source". Throughout the following years, they re-licensed all [https://www.isc.org/download ISC-hosted] software, including BIND in 2016<ref>{{Cite web|title=BIND 9 Adopts the MPL 2.0 License with BIND 9.11.0 - Internet Systems Consortium|url=https://www.isc.org/blogs/bind9-adopts-the-mpl-2-0-license-with-bind-9-11-0/|access-date=2020-07-18|website=www.isc.org|date=27 June 2016 }}</ref> and ISC DHCP Server in 2017.<ref>{{Cite web|title=ISC DHCP Moves to MPL 2.0 License - Internet Systems Consortium|url=https://www.isc.org/blogs/isc-dhcp-moves-to-mpl-2-0-license/|access-date=2020-07-18|website=www.isc.org|date=19 June 2017 }}</ref>

The Publications Office of the European Union advises using the MIT license instead of the ISC License in order to reduce [[license proliferation]].<ref>{{Cite web|title=ISC License (ISC) - EU Vocabularies - Publications Office of the EU|url=https://op.europa.eu/en/web/eu-vocabularies/concept/-/resource?uri=http://publications.europa.eu/resource/authority/licence/ISC|access-date=2020-07-18|website=op.europa.eu}}</ref>

The GNU project states the inclusion of "and/or" still allows the license to be interpreted as prohibiting distribution of modified versions. Although they state there is no reason to avoid software released under this license, they advise against using the license to keep the problematic language from causing trouble in the future.<ref>{{Cite web |title=Various Licenses and Comments about Them |url=https://www.gnu.org/licenses/license-list.en.html#ISC |access-date=2020-07-18 |website=www.gnu.org |language=en}}</ref>

== See also ==
{{Portal|Free and open-source software}}
* [[Comparison of free and open-source software licenses]]
* [[:Category:Software using the ISC license|Software using the ISC license]]

== Footnotes ==
{{Reflist|group=nb}}

== References ==
{{Reflist|refs=
<ref name="openbsd-policy">{{cite web
  | url        = http://www.openbsd.org/policy.html
  | title      = Copyright Policy
  | work       = [[OpenBSD]]
  | access-date = 6 June 2016
  }}</ref>
<ref name="theo2008">{{cite mailing list
  | url          = https://marc.info/?l=openbsd-misc&m=120618313520730&w=2
  | title        = Re: BSD Documentation License?
  | mailing-list = openbsd-misc
  | last         = de Raadt
  | first        = Theo
  | author-link   = Theo de Raadt
  | date         = 21 March 2008
  | access-date   = 17 March 2017
  }}</ref>
<ref name="openbsd-license-template">{{cite web
  | url        = http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/share/misc/license.template?rev=HEAD
  | title      = OpenBSD license template
  | access-date = 17 March 2017
  }}</ref>
<ref name="npm-commit">{{cite web
  | url        = https://github.com/npm/init-package-json/pull/9
  | title      = Update default license to ISC
  | at         = Pull Request #9
  | work       = npm/init-package-json
  | first      = Tim
  | last       = Oxley
  | date       = 8 January 2014
  | access-date = 17 March 2017
  }}</ref>
}}

== External links ==
* [http://www.isc.org/downloads/software-support-policy/isc-license/ Internet Systems Consortium's License Text]
* [http://opensource.org/licenses/ISC License template at the Open Source Initiative]

{{FOSS}}

{{DEFAULTSORT:Isc License}}
[[Category:Free and open-source software licenses]]
[[Category:Permissive software licenses]]