1# The LaTeX Project Public License23LPPL Version 1.3c 2008-05-0445Copyright 1999 2002-2008 LaTeX3 Project6 Everyone is allowed to distribute verbatim copies of this7 license document, but modification of it is not allowed.8910## PREAMBLE1112The LaTeX Project Public License (LPPL) is the primary license under13which the LaTeX kernel and the base LaTeX packages are distributed.1415You may use this license for any work of which you hold the copyright16and which you wish to distribute. This license may be particularly17suitable if your work is TeX-related (such as a LaTeX package), but18it is written in such a way that you can use it even if your work is19unrelated to TeX.2021The section `WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE',22below, gives instructions, examples, and recommendations for authors23who are considering distributing their works under this license.2425This license gives conditions under which a work may be distributed26and modified, as well as conditions under which modified versions of27that work may be distributed.2829We, the LaTeX3 Project, believe that the conditions below give you30the freedom to make and distribute modified versions of your work31that conform with whatever technical specifications you wish while32maintaining the availability, integrity, and reliability of33that work. If you do not see how to achieve your goal while34meeting these conditions, then read the document `cfgguide.tex'35and `modguide.tex' in the base LaTeX distribution for suggestions.363738## DEFINITIONS394041In this license document the following terms are used:4243 `Work'44 Any work being distributed under this License.4546 `Derived Work'47 Any work that under any applicable law is derived from the Work.4849 `Modification'50 Any procedure that produces a Derived Work under any applicable51 law -- for example, the production of a file containing an52 original file associated with the Work or a significant portion of53 such a file, either verbatim or with modifications and/or54 translated into another language.5556 `Modify'57 To apply any procedure that produces a Derived Work under any58 applicable law.5960 `Distribution'61 Making copies of the Work available from one person to another, in62 whole or in part. Distribution includes (but is not limited to)63 making any electronic components of the Work accessible by64 file transfer protocols such as FTP or HTTP or by shared file65 systems such as Sun's Network File System (NFS).6667 `Compiled Work'68 A version of the Work that has been processed into a form where it69 is directly usable on a computer system. This processing may70 include using installation facilities provided by the Work,71 transformations of the Work, copying of components of the Work, or72 other activities. Note that modification of any installation73 facilities provided by the Work constitutes modification of the Work.7475 `Current Maintainer'76 A person or persons nominated as such within the Work. 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Should the Work prove defective, you assume212the cost of all necessary servicing, repair, or correction.213214In no event unless required by applicable law or agreed to in writing215will The Copyright Holder, or any author named in the components of the216Work, or any other party who may distribute and/or modify the Work as217permitted above, be liable to you for damages, including any general,218special, incidental or consequential damages arising out of any use of219the Work or out of inability to use the Work (including, but not limited220to, loss of data, data being rendered inaccurate, or losses sustained by221anyone as a result of any failure of the Work to operate with any other222programs), even if the Copyright Holder or said author or said other223party has been advised of the possibility of such damages.224225226## MAINTENANCE OF THE WORK227228229The Work has the status `author-maintained' if the Copyright Holder230explicitly and prominently states near the primary copyright notice in231the Work that the Work can only be maintained by the Copyright Holder232or simply that it is `author-maintained'.233234The Work has the status `maintained' if there is a Current Maintainer235who has indicated in the Work that they are willing to receive error236reports for the Work (for example, by supplying a valid e-mail237address). 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You should also294announce your new status to the same pertinent community as295in 2b) above.296297298## WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE299300301This section contains important instructions, examples, and302recommendations for authors who are considering distributing their303works under this license. These authors are addressed as `you' in304this section.305306### Choosing This License or Another License307308If for any part of your work you want or need to use *distribution*309conditions that differ significantly from those in this license, then310do not refer to this license anywhere in your work but, instead,311distribute your work under a different license. You may use the text312of this license as a model for your own license, but your license313should not refer to the LPPL or otherwise give the impression that314your work is distributed under the LPPL.315316The document `modguide.tex' in the base LaTeX distribution explains317the motivation behind the conditions of this license. It explains,318for example, why distributing LaTeX under the GNU General Public319License (GPL) was considered inappropriate. Even if your work is320unrelated to LaTeX, the discussion in `modguide.tex' may still be321relevant, and authors intending to distribute their works under any322license are encouraged to read it.323324### A Recommendation on Modification Without Distribution325326It is wise never to modify a component of the Work, even for your own327personal use, without also meeting the above conditions for328distributing the modified component. While you might intend that such329modifications will never be distributed, often this will happen by330accident -- you may forget that you have modified that component; or331it may not occur to you when allowing others to access the modified332version that you are thus distributing it and violating the conditions333of this license in ways that could have legal implications and, worse,334cause problems for the community. It is therefore usually in your335best interest to keep your copy of the Work identical with the public336one. Many works provide ways to control the behavior of that work337without altering any of its licensed components.338339### How to Use This License340341To use this license, place in each of the components of your work both342an explicit copyright notice including your name and the year the work343was authored and/or last substantially modified. Include also a344statement that the distribution and/or modification of that345component is constrained by the conditions in this license.346347Here is an example of such a notice and statement:348349 %% pig.dtx350 %% Copyright 2005 M. Y. Name351 %352 % This work may be distributed and/or modified under the353 % conditions of the LaTeX Project Public License, either version 1.3354 % of this license or (at your option) any later version.355 % The latest version of this license is in356 % http://www.latex-project.org/lppl.txt357 % and version 1.3 or later is part of all distributions of LaTeX358 % version 2005/12/01 or later.359 %360 % This work has the LPPL maintenance status `maintained'.361 %362 % The Current Maintainer of this work is M. Y. Name.363 %364 % This work consists of the files pig.dtx and pig.ins365 % and the derived file pig.sty.366367Given such a notice and statement in a file, the conditions368given in this license document would apply, with the `Work' referring369to the three files `pig.dtx', `pig.ins', and `pig.sty' (the last being370generated from `pig.dtx' using `pig.ins'), the `Base Interpreter'371referring to any `LaTeX-Format', and both `Copyright Holder' and372`Current Maintainer' referring to the person `M. Y. Name'.373374If you do not want the Maintenance section of LPPL to apply to your375Work, change `maintained' above into `author-maintained'.376However, we recommend that you use `maintained', as the Maintenance377section was added in order to ensure that your Work remains useful to378the community even when you can no longer maintain and support it379yourself.380381### Derived Works That Are Not Replacements382383Several clauses of the LPPL specify means to provide reliability and384stability for the user community. They therefore concern themselves385with the case that a Derived Work is intended to be used as a386(compatible or incompatible) replacement of the original Work. If387this is not the case (e.g., if a few lines of code are reused for a388completely different task), then clauses 6b and 6d shall not apply.389390391### Important Recommendations392393 Defining What Constitutes the Work394395 The LPPL requires that distributions of the Work contain all the396 files of the Work. It is therefore important that you provide a397 way for the licensee to determine which files constitute the Work.398 This could, for example, be achieved by explicitly listing all the399 files of the Work near the copyright notice of each file or by400 using a line such as:401402 % This work consists of all files listed in manifest.txt.403404 in that place. In the absence of an unequivocal list it might be405 impossible for the licensee to determine what is considered by you406 to comprise the Work and, in such a case, the licensee would be407 entitled to make reasonable conjectures as to which files comprise408 the Work.