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Software license

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A software license is a legal instrument (usually by way of contract law, with or without printed material) governing the use or redistribution of software. All software is copyright protected, except material in the public domain. Contractual confidentiality is another way of protecting software. A typical software license grants an end-user permission to use one or more copies of software in ways where such a use would otherwise potentially constitute copyright infringement of the software owner's exclusive rights under copyright law.

In addition to granting rights and imposing restrictions on the use of software, software licenses typically contain provisions which allocate liability and responsibility between the parties entering into the license agreement. In enterprise and commercial software transactions these terms (such as limitations of liability, warranties and warranty disclaimers, and indemnity if the software infringes intellectual property rights of others) are often negotiated by attorneys specialized in software licensing. The legal field has seen the growth of this specialized practice area due to unique legal issues with software licenses, and the desire of software companies to protect assets which, if licensed improperly, could diminish their value.

Software licenses can vary immensely, as software developers can place whatever conditions of use on their software as they so desire, within legal limitations, of course. Different conditions may apply to the source and binary forms of software.

In the United States, Section 117 of the Copyright Act gives the owner of a particular copy of software the explicit right to use the software with a computer, even if use of the software with a computer requires the making of incidental copies or adaptations (acts which could otherwise potentially constitute copyright infringement). Therefore, the owner of a copy of computer software is legally entitled to use that copy of software. Hence, if the end-user of software is the owner of the respective copy, then the end-user may legally use the software without a license from the software publisher.

As many proprietary "licenses" only enumerate the rights that the user already has under 17 U.S.C. § 117, and yet proclaim to take rights away from the user, these contracts may lack consideration. Proprietary software licenses often proclaim to give software publishers more control over the way their software is used by keeping ownership of each copy of software with the software publisher. By doing so, Section 117 does not apply to the end-user and the software publisher may then compel the end-user to accept all of the terms of the license agreement, many of which may be more restrictive than copyright law alone. It should be noticed that the form of the relationship determines if it is a lease or a purchase, for example UMG v. Augusto[1] or Vernor v. Autodesk, Inc.[2][3]

Permissive and restrictive software licenses

Software licenses can be categorized, in one way, according to their degree of permissiveness and restrictiveness. Some software licenses, e.g., impose minimal requirements upon users about how the software can be used, modified and redistributed (permissive licenses), while others impose more than just minimal conditions of use upon users about how the software can be used, modified and redistributed (restrictive licenses).

Software licenses which are sold (for profit or not for profit), are restrictive so that the profit or recovery of development costs goals are not undermined. To further prevent undermining of the software developer's goals, software licenses which are sold are usually associated with software for which the source is not made available to end-users. Software licenses which are not sold, can span the range from permissive to restrictive. For examples, the BSD license and MIT license impart few conditions of use upon software and are therefore permissive, while the Microsoft Windows EULA and the GNU GPL impart a number of conditions of use upon software and are therefore restrictive.

Closed-source software licenses

Main article: Proprietary software
Further information: End-user license agreement

The hallmark of closed-source software licenses is that the software publisher grants the use of one or more copies of software under the end-user license agreement (EULA), but ownership of those copies remains with the software publisher (hence use of the term "proprietary"). This feature of closed-source software licenses means that certain rights regarding the software are reserved by the software publisher. Therefore, it is typical of EULAs to include terms which define the uses of the software, such as the number of installations allowed or the terms of distribution.

The most significant effect of this form of licensing is that, if ownership of the software remains with the software publisher, then the end-user must accept the software license. In other words, without acceptance of the license, the end-user may not use the software at all. One example of such a proprietary software license is the license for Microsoft Windows. As is usually the case with proprietary software licenses, this license contains an extensive list of activities which are restricted, such as: reverse engineering, simultaneous use of the software by multiple users, and publication of benchmarks or performance tests.

The most common licensing models is per single user (named user, client, node) or per user in the appropriate volume discount level, while some manufacturers accumulate existing licenses. These open volume license programs are typically called Open License Program (OLP), Transactional License Program (TLP), Volume License Program (VLP) etc. and are contrary to the Contractual License Program (CLP), where the customer commits to purchase a certain amount of licenses over a fixed period (mostly two years). Licensing per concurrent/floating user also occurs, where all users in a network have access to the program, but only a specific number at the same time. Another license model is licensing per dongle which allows the owner of the dongle to use the program on any computer. Licensing per server, CPU or points, regardless the number of users, is common practice as well as Site or Company Licenses. Sometimes you can choose between perpetual (permanent) and annual license. For perpetual licenses one year of maintenance is often required, but maintenance (subscription) renewals are discounted. For annual licenses, there is no Renewal, a new license must be purchased after expiration. Licensing can be Host/Client (or Guest), Mailbox, IP-Address, Domain etc., depending on how the program is used. Additional users are inter alia licensed per Extension Pack (e.g. up to 99 user), which includes the Base Pack (e.g. 5 user). Some programs are modular, so you have to buy a base product before you can use other modules.[4]

Software licensing also includes maintenance. This, usually with a term of one year, is either included or optional, but must often be bought with the software. The maintenance agreement (contract) contains Minor Updates (V.1.1 => 1.2), sometimes Major Updates (V.1.2 => 2.0) and is called e.g. Update Insurance, Upgrade Assurance. For a Major Update the customer has to buy an Upgrade, if not included in the maintenance. For a maintenance renewal some manufacturers charge a Reinstatement (Reinstallment) Fee retroactively per month, in case the current maintenance has expired. Maintenance normally doesn't include technical support. Here you differentiate between e-mail and tel. support, also availability (e.g. 5x8, 5 days a week, 8 hours a day) and reaction time (e.g. three hours) can play a role. This is commonly named Gold, Silver and Bronze Support. Support is also licensed per incident as Incident Pack (e.g. five support incidents per year).[4]

Many manufacturers offer special conditions for schools and government agencies (EDU/GOV License). Migration from another product (Crossgrade), even from a different manufacturer (Competitive Upgrade) is offered.[4]

Open-source software licenses

Main articles: Free software license and Open source software license

FSF-approved "free software" licenses

Free Software Foundation, the group that maintains The Free Software Definition, maintains a non-exhaustive list of free software licenses.[5] The list distinguishes between free software licenses that are compatible or incompatible with the FSF license of choice, the GNU General Public License, which is a copyleft license. The list also contains licenses which the FSF considers non-free for various reasons, but which are sometimes mistaken as being free.

Further information: List of FSF approved software licenses

OSI-approved "open source" licenses

The group Open Source Initiative (OSI) defines and maintains a list of approved open source licenses. OSI agrees with FSF on all widely used free software licenses, but differ from FSF's list since the two organizations have different requirement for approving licenses.

Further information: List of OSI approved software licenses

BSD-style licenses

The BSD license and the MIT license, give unlimited permission to use, study, and privately modify the software, and include only minimal requirements on redistribution. This gives a user the permission to take the code and use it as part of closed-source software or software released under a proprietary software license.

Essentially, the BSD license's only requirement is to acknowledge the original authors, and poses no restrictions on how the source code may be used. As a result, BSD code can be used in proprietary software that only acknowledges the authors. For instance, the IP stack in Microsoft Windows NT 3.1 and Mac OS X are derived from BSD-licensed software.

GPL-style licenses

GNU General Public License-style (GPL) licenses, also knows as "copyleft" licenses, allow the end-user to use, study, and privately modify the software without accepting the license. However, if the user wishes to distribute the software, then the end-user must accept the conditions given in the software license. The GPL requires any derivative work to also be released according to the GPL. [6]

BSD-style license vs. GPL-style license issues

Supporters of the BSD license assert that it is more permissive (or, then, less restrictive) than the GPL because it allows users to use the source code with minimal conditions of use. They hold that BSD-licensed software is second only to software in the public domain software in regards to minimal conditions of use. An assertion is made that GPL-style licenses, particularly the GNU General Public License (GPL), are undesirably complicated and/or restrictive.

BSD-licensed source code can be incorporated into proprietary products, leading to BSD code being used in common, widely used proprietary software. Supporters of the GPL license are against allowing the use of permissively-licensed source code in closed-source software. [7]

Source code licensed under a permissive software license, such as the BSD license, can be incorporated into source code licensed under the restrictive GPL license. Such code is thus "GPL-compatible". There is no need to secure the consent of the original authors. In contrast, code under the GPL cannot be relicensed under the BSD license without securing the consent of all copyright holders. Thus the two licenses are only one-way-compatible, for the combination as a whole in the former scenario must be distributed under the terms of the GPL, and not the permissive license.

Many users and developers of BSD-based operating systems have a different positions on licensing. Existing free software BSDs tend to avoid including software licensed under the GPL in the core operating system, or the base system, except as a last resort when alternatives are non-existent or vastly less capable, such as with GCC. (Indeed however, note that as of mid 2010 FreeBSD for example are moving from GCC to the upcoming LLVM compiler, perhaps primarily for this reason.) The OpenBSD project has acted to remove GPL-licensed tools in favor of BSD-licensed alternatives, some newly written and some adapted from older code.

See also

References

  1. ^ "UMG v. Augusto". January 28, 2009.
  2. ^ "Court smacks Autodesk, affirms right to sell used software". May 23, 2008.
  3. ^ "Vernor v. Autodesk". 2007-11-14.
  4. ^ a b c Scholten, Thomas. "Software Licensing". Retrieved 21 May 2012.
  5. ^ License list - Free Software Foundation
  6. ^ "OpenBSD Copyright Policy". the restriction that source code must be distributed or made available for all works that are derivatives [...] As a consequence, software bound by the GPL terms cannot be included in the kernel or "runtime" of OpenBSD
  7. ^ "Freedom or Power? by Bradley Kuhn and Richard Stallman".
Wikibooks has a book on the topic of: FOSS Licensing
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