Why you should use a bsd style license for your open source project. It was first used in 1980 for the berkeley source distribution bsd, also known as bsd unix, an enhanced version of the original unix operating system that was first. We provide below is a little explanation of copyleft versus non. What is the difference between a bsd and a gpl license types. In general copyleft licenses are compatible with other opensource licenses as long as. Copyleft is a distinguishing feature of some free software licenses. Various licenses and comments about them gnu project. Nov 21, 2014 as software developers and publishers, when it comes to integrating third party software, we have to look carefully at the license. The apache license is a permissive open source software license so you can.
In addition, the clause presented a legal problem for those wishing to publish bsdlicensed software which relies upon separate programs using the gnu gpl. Open source licenses are licenses that comply with the open source definition in brief, they allow software to be freely used, modified, and shared. Holders of the mit license can produce, without restrictions, any derivative works from the original software and even reap commercial benefits. Copyleft basically means that any modifications you make to a piece of copyleftlicensed software have to be released under the same conditions as the original software. Oct 16, 2019 instead, copyleft license rules require all derivative works to be subject to the original license.
The following licenses are sorted by the number of conditions, from most gnu agplv3 to none unlicense. The gpl license is copyleft, therefore you must disclose your source code and make your modified version of your code open source as well. The open source initiative defines a permissive software license as a noncopyleft license. The gnu project gives this simple definition of copyleft. Not unlike software in the public domain, these noncopyleft licenses usually grant software freedom to users, but they do not go to any effort to. Software can become incompatible with secondary licenses in one of two ways. Apr 19, 2004 the bsd license is a class of extremely simple and very liberal licenses for computer software that was originally developed at the university of california at berkeley ucb.
The original bsd license is also one of the first freesoftware licenses, dating to 1988. There are many variants of simple noncopyleft free software licenses, such as the expat license, freebsd license, x10 license, the x11 license, and the two bsd berkeley software distribution licenses. This is in distinction to permissive free software licenses like the bsd licenses and the mit. Copycenter is a term originally used to explain the modified bsd licence, a permissive freesoftware license. Since our products are commercial and not free our code is closed, we only integrate third party software that have noncopyleft license. If you make a modification to a program licensed under the gpl the modification also needs to be gpl. This can be considered the canonical definition, since the gnu general public license gpl in its various versions remains the most widelyused. There are 3 bsd licenses, but only two accepted and recommended by the open source initiative and the fsf. Microsoft and apple seem to be allowed to take bsd or similar licensed code and distribute it under a proprietary license. In 1989, version 1 of the gnu general public license gpl was published. Questions about the in a license should be directed to the license steward.
Nov 05, 2015 bsd licenses or the original bsd license and its two variants the modified license 3clause, and the simplified licensefreebsd license 2clause are a family of permissive free software licenses. It is nearly identical to the freebsd also called 2clause bsd license. From this family, the most common licenses are the 3clause bsd license and the 2clause license. If the copyleft software becomes part of a larger software product, and the licensee distributes that product, it has to distribute the whole thing as. Copyleft licenses like gpl are, generally speaking, bad for business. Dec 05, 2017 a copyleft license means the derivative work can only be distributed under the same license terms. Examples of noncopyleft permissive freesoftware licenses include the x11 license, apache license and the bsd licenses. This is in contrast to copyleft licenses, which have sharealike requirements. The original bsd license was used for its namesake, the berkeley software distribution bsd, a unixlike operating system. Examples include the mit license, bsd licenses, apple public source license and the apache license. If you interpret bsd licenses as referring to the more commonly used 3clause or 2clause variants of the bsd license, all five claims in the question are true. Software unter bsdlizenz darf frei verwendet werden. The earliest license to grant software freedom was likely the berkeley software distribution bsd license.
This is in contrast to copyleft licenses like the gpl, which have reciprocity sharealike requirements. A permissive software license, sometimes also called bsdlike or bsdstyle license, is a. At that time computer companies were in the hardware business. Nov 05, 2018 copyleft licenses require that all modification to the original software or software based, even in part, on the original must to be released under the same open source license as the original and must therefore be open source themselves. See how to choose a license for your own work for general recommendations about choosing a license for your work the two major categories of free software license are copyleft and non copyleft. Bsd fourclause licensethe original 1990 berkeley software distribution license allowed for free. The berkley software distribution licenses is a non copyleft, permissive license. The gpl is a copyleft license, meaning that any derivative. Whitesource concluded that use of permissive opensource licenses continues to rise, while usage of copyleft licenses, and the gplfamily in particular, continues to decrease. Without an open source license, the software component is unusable by others. Various licenses and comments about them gnu project free.
Top 10 apache license questions answered whitesource. The term was presented by computer scientist and berkeley software distribution bsd contributor marshall kirk mckusick at a bsd conference in 1999. The original bsd license4clause is not accepted as an open. Most of them are equivalent except for details of wording, but the license used for bsd until 1999 had a special problem. Permissive software license wikipedia republished wiki 2. Free software licenses can be divided into two broad categories. Using dynamically linked library with bsd 3clause license. If a bsd licensed program becomes orphaned, a company can simply take over, in a proprietary manner, the program on which they are dependent. A copyleft license may be strong or weaka strong copyleft license covers both the. The two licenses are very different from each other. Previous apache versions, being heavily based on the bsd license, are. Aug 15, 2015 mozilla public license mpl the mozilla foundation ls the custodian of the mozilla public ucense mpl.
The free software foundation call the gplstyle restrictions you must release any modifications under the same licence copyleft. So if i write program b based on program a and program a has a copyleft type license, then i must also. Why dash uses the mit license and not a copyleft gpl license. Bsd license problem gnu project free software foundation. This means that developers cannot make patent or claims on the original software. Sep 24, 2019 bsd berkeley software distribution is a permissive license that initially consisted of 4 chapters, but later the chapter. One of the main differences between a gnu general public license gnu gpl or simply gpl, the most common type of license for free software, and a bsd license is that gpl are copyleft, meaning any derivative code produced from the original free open source code must remain free.
Use of the term bsd license refers to licenses that use versions of a bsd license as a template. The mpl has a limited amount of copyleft terms, more than the bsd family of licenses, but fewer than the lpgl or the gpl. They require all modifications, and any software based on the open source component, even in a small part, to be released under an open source license. The differences between the gpl, lgpl and the bsd fosswire. The problem for traditional proprietary software distributors gets worse from there. Bsd licenses are a low restriction type of license for open source software that. Understanding opensource and free software licensing. A permissive software license, sometimes also called bsd like or bsd style license, is a free software software license with minimal requirements about how the software can be redistributed. If all of the above is correct, then what is the point of using a dual mit bsd. It is a lax, permissive noncopyleft free software license, compatible with the gnu gpl.
This license is typical of what are often called lax, highly permissive licenses. Can i take bsd licensed code and distribute it under gpl. Open source licenses grant permission for anybody to use, modify, and share licensed software for any purpose, subject to conditions preserving the provenance and openness of the software. The copyleft licenses for software require the necessary information to. Many free software licenses are not copyleft licenses because they do not require the licensee to distribute derivative works under the same license. The permissive software license, sometimes also called bsdlike or. There are variations, of coursethe lgpl, for example, is a weak copyleft. The revised bsd license3 clause, and the simplified bsd license2clause. Why you should use a bsd style license for your open source. Mr stallman himself has an essay about this and other issues on the gnu site.
The revised bsd license 3 clause, and the simplified bsd license 2clause. Bsd licenses are a family of permissive free software licenses, imposing minimal restrictions on the redistribution of covered software. A bsd license gives a small company the equivalent of software inescrow without any legal complications or costs. This is a lax, permissive noncopyleft free software license, compatible with the gnu gpl. The original bsd license was used for its namesake, the berkeley software. Copyleft basically means that any modifications you make to a piece of copyleft licensed software have to be released under the same conditions as the original software. Jan 26, 2018 the bestknown copyleft license is the general public license, or gpl, from the free software foundation. Bear in mind though, this article does push stallmans personal views on software licences quite heavily. Should you use a gnu gpl or mit open source license. Due to their permissive nature, they have very relaxed conditions about redistributing software licensed under them. These licenses are compatible with free opensource software licenses and proprietary software licenses. The content on this website, of which is the author, is licensed under a creative commons attribution 4. Software licensing part ii a deeper dive into license types. In contrast to a strong copyleft, nonpermissive license like the gpl the bsd licenses are instead non copyleft and permissive.
The other answer seems to be assuming you are including the older, rarely used 4 clause bsd license. Can i take code which is licensed under a permissive open source license like the bsd license and distribute it under a copyleft free software license like the gpl. Bsd licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. A data scientists guide to open source licensing towards.
Under the mpl, the copyleft terms apply to any modifications you make to an mpl file or any file that contains any part of the original mpl code. Two classes of licenses have emerged over the years, copyleft and bsdstyle licenses. Apr 16, 2020 by 2019, 33 percent of the software in the whitesource data set relied on copyleft licenses while 67 percent of the software favored a permissive opensource license. The 3clause modified bsd license includes a nonendorsement clause, which says users dont have the right to market software using bsdlicensed components in such a way that their product appears to be endorsed by the original developers. Copyleft licenses such as the gnu gpl insist that modified versions of the program must be free software as well. Version 2 of the gpl, released in 1991, went on to become the most widely used freesoftware license. According to research by white source, the most popular permissive licenses are mit and apache 2. There is an ongoing debate as to which class of license provides the greater degree of freedom.
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