| 1 | The LaTeX Project Public License |
| 2 | =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- |
| 3 | |
| 4 | LPPL Version 1.3c 2008-05-04 |
| 5 | |
| 6 | Copyright 1999 2002-2008 LaTeX3 Project |
| 7 | Everyone is allowed to distribute verbatim copies of this |
| 8 | license document, but modification of it is not allowed. |
| 9 | |
| 10 | |
| 11 | PREAMBLE |
| 12 | ======== |
| 13 | |
| 14 | The LaTeX Project Public License (LPPL) is the primary license under |
| 15 | which the LaTeX kernel and the base LaTeX packages are distributed. |
| 16 | |
| 17 | You may use this license for any work of which you hold the copyright |
| 18 | and which you wish to distribute. This license may be particularly |
| 19 | suitable if your work is TeX-related (such as a LaTeX package), but |
| 20 | it is written in such a way that you can use it even if your work is |
| 21 | unrelated to TeX. |
| 22 | |
| 23 | The section `WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE', |
| 24 | below, gives instructions, examples, and recommendations for authors |
| 25 | who are considering distributing their works under this license. |
| 26 | |
| 27 | This license gives conditions under which a work may be distributed |
| 28 | and modified, as well as conditions under which modified versions of |
| 29 | that work may be distributed. |
| 30 | |
| 31 | We, the LaTeX3 Project, believe that the conditions below give you |
| 32 | the freedom to make and distribute modified versions of your work |
| 33 | that conform with whatever technical specifications you wish while |
| 34 | maintaining the availability, integrity, and reliability of |
| 35 | that work. If you do not see how to achieve your goal while |
| 36 | meeting these conditions, then read the document `cfgguide.tex' |
| 37 | and `modguide.tex' in the base LaTeX distribution for suggestions. |
| 38 | |
| 39 | |
| 40 | DEFINITIONS |
| 41 | =========== |
| 42 | |
| 43 | In this license document the following terms are used: |
| 44 | |
| 45 | `Work' |
| 46 | Any work being distributed under this License. |
| 47 | |
| 48 | `Derived Work' |
| 49 | Any work that under any applicable law is derived from the Work. |
| 50 | |
| 51 | `Modification' |
| 52 | Any procedure that produces a Derived Work under any applicable |
| 53 | law -- for example, the production of a file containing an |
| 54 | original file associated with the Work or a significant portion of |
| 55 | such a file, either verbatim or with modifications and/or |
| 56 | translated into another language. |
| 57 | |
| 58 | `Modify' |
| 59 | To apply any procedure that produces a Derived Work under any |
| 60 | applicable law. |
| 61 | |
| 62 | `Distribution' |
| 63 | Making copies of the Work available from one person to another, in |
| 64 | whole or in part. Distribution includes (but is not limited to) |
| 65 | making any electronic components of the Work accessible by |
| 66 | file transfer protocols such as FTP or HTTP or by shared file |
| 67 | systems such as Sun's Network File System (NFS). |
| 68 | |
| 69 | `Compiled Work' |
| 70 | A version of the Work that has been processed into a form where it |
| 71 | is directly usable on a computer system. This processing may |
| 72 | include using installation facilities provided by the Work, |
| 73 | transformations of the Work, copying of components of the Work, or |
| 74 | other activities. Note that modification of any installation |
| 75 | facilities provided by the Work constitutes modification of the Work. |
| 76 | |
| 77 | `Current Maintainer' |
| 78 | A person or persons nominated as such within the Work. If there is |
| 79 | no such explicit nomination then it is the `Copyright Holder' under |
| 80 | any applicable law. |
| 81 | |
| 82 | `Base Interpreter' |
| 83 | A program or process that is normally needed for running or |
| 84 | interpreting a part or the whole of the Work. |
| 85 | |
| 86 | A Base Interpreter may depend on external components but these |
| 87 | are not considered part of the Base Interpreter provided that each |
| 88 | external component clearly identifies itself whenever it is used |
| 89 | interactively. Unless explicitly specified when applying the |
| 90 | license to the Work, the only applicable Base Interpreter is a |
| 91 | `LaTeX-Format' or in the case of files belonging to the |
| 92 | `LaTeX-format' a program implementing the `TeX language'. |
| 93 | |
| 94 | |
| 95 | |
| 96 | CONDITIONS ON DISTRIBUTION AND MODIFICATION |
| 97 | =========================================== |
| 98 | |
| 99 | 1. Activities other than distribution and/or modification of the Work |
| 100 | are not covered by this license; they are outside its scope. In |
| 101 | particular, the act of running the Work is not restricted and no |
| 102 | requirements are made concerning any offers of support for the Work. |
| 103 | |
| 104 | 2. You may distribute a complete, unmodified copy of the Work as you |
| 105 | received it. Distribution of only part of the Work is considered |
| 106 | modification of the Work, and no right to distribute such a Derived |
| 107 | Work may be assumed under the terms of this clause. |
| 108 | |
| 109 | 3. You may distribute a Compiled Work that has been generated from a |
| 110 | complete, unmodified copy of the Work as distributed under Clause 2 |
| 111 | above, as long as that Compiled Work is distributed in such a way that |
| 112 | the recipients may install the Compiled Work on their system exactly |
| 113 | as it would have been installed if they generated a Compiled Work |
| 114 | directly from the Work. |
| 115 | |
| 116 | 4. If you are the Current Maintainer of the Work, you may, without |
| 117 | restriction, modify the Work, thus creating a Derived Work. You may |
| 118 | also distribute the Derived Work without restriction, including |
| 119 | Compiled Works generated from the Derived Work. Derived Works |
| 120 | distributed in this manner by the Current Maintainer are considered to |
| 121 | be updated versions of the Work. |
| 122 | |
| 123 | 5. If you are not the Current Maintainer of the Work, you may modify |
| 124 | your copy of the Work, thus creating a Derived Work based on the Work, |
| 125 | and compile this Derived Work, thus creating a Compiled Work based on |
| 126 | the Derived Work. |
| 127 | |
| 128 | 6. If you are not the Current Maintainer of the Work, you may |
| 129 | distribute a Derived Work provided the following conditions are met |
| 130 | for every component of the Work unless that component clearly states |
| 131 | in the copyright notice that it is exempt from that condition. Only |
| 132 | the Current Maintainer is allowed to add such statements of exemption |
| 133 | to a component of the Work. |
| 134 | |
| 135 | a. If a component of this Derived Work can be a direct replacement |
| 136 | for a component of the Work when that component is used with the |
| 137 | Base Interpreter, then, wherever this component of the Work |
| 138 | identifies itself to the user when used interactively with that |
| 139 | Base Interpreter, the replacement component of this Derived Work |
| 140 | clearly and unambiguously identifies itself as a modified version |
| 141 | of this component to the user when used interactively with that |
| 142 | Base Interpreter. |
| 143 | |
| 144 | b. Every component of the Derived Work contains prominent notices |
| 145 | detailing the nature of the changes to that component, or a |
| 146 | prominent reference to another file that is distributed as part |
| 147 | of the Derived Work and that contains a complete and accurate log |
| 148 | of the changes. |
| 149 | |
| 150 | c. No information in the Derived Work implies that any persons, |
| 151 | including (but not limited to) the authors of the original version |
| 152 | of the Work, provide any support, including (but not limited to) |
| 153 | the reporting and handling of errors, to recipients of the |
| 154 | Derived Work unless those persons have stated explicitly that |
| 155 | they do provide such support for the Derived Work. |
| 156 | |
| 157 | d. You distribute at least one of the following with the Derived Work: |
| 158 | |
| 159 | 1. A complete, unmodified copy of the Work; |
| 160 | if your distribution of a modified component is made by |
| 161 | offering access to copy the modified component from a |
| 162 | designated place, then offering equivalent access to copy |
| 163 | the Work from the same or some similar place meets this |
| 164 | condition, even though third parties are not compelled to |
| 165 | copy the Work along with the modified component; |
| 166 | |
| 167 | 2. Information that is sufficient to obtain a complete, |
| 168 | unmodified copy of the Work. |
| 169 | |
| 170 | 7. If you are not the Current Maintainer of the Work, you may |
| 171 | distribute a Compiled Work generated from a Derived Work, as long as |
| 172 | the Derived Work is distributed to all recipients of the Compiled |
| 173 | Work, and as long as the conditions of Clause 6, above, are met with |
| 174 | regard to the Derived Work. |
| 175 | |
| 176 | 8. The conditions above are not intended to prohibit, and hence do not |
| 177 | apply to, the modification, by any method, of any component so that it |
| 178 | becomes identical to an updated version of that component of the Work as |
| 179 | it is distributed by the Current Maintainer under Clause 4, above. |
| 180 | |
| 181 | 9. Distribution of the Work or any Derived Work in an alternative |
| 182 | format, where the Work or that Derived Work (in whole or in part) is |
| 183 | then produced by applying some process to that format, does not relax or |
| 184 | nullify any sections of this license as they pertain to the results of |
| 185 | applying that process. |
| 186 | |
| 187 | 10. a. A Derived Work may be distributed under a different license |
| 188 | provided that license itself honors the conditions listed in |
| 189 | Clause 6 above, in regard to the Work, though it does not have |
| 190 | to honor the rest of the conditions in this license. |
| 191 | |
| 192 | b. If a Derived Work is distributed under a different license, that |
| 193 | Derived Work must provide sufficient documentation as part of |
| 194 | itself to allow each recipient of that Derived Work to honor the |
| 195 | restrictions in Clause 6 above, concerning changes from the Work. |
| 196 | |
| 197 | 11. This license places no restrictions on works that are unrelated to |
| 198 | the Work, nor does this license place any restrictions on aggregating |
| 199 | such works with the Work by any means. |
| 200 | |
| 201 | 12. Nothing in this license is intended to, or may be used to, prevent |
| 202 | complete compliance by all parties with all applicable laws. |
| 203 | |
| 204 | |
| 205 | NO WARRANTY |
| 206 | =========== |
| 207 | |
| 208 | There is no warranty for the Work. Except when otherwise stated in |
| 209 | writing, the Copyright Holder provides the Work `as is', without |
| 210 | warranty of any kind, either expressed or implied, including, but not |
| 211 | limited to, the implied warranties of merchantability and fitness for a |
| 212 | particular purpose. The entire risk as to the quality and performance |
| 213 | of the Work is with you. Should the Work prove defective, you assume |
| 214 | the cost of all necessary servicing, repair, or correction. |
| 215 | |
| 216 | In no event unless required by applicable law or agreed to in writing |
| 217 | will The Copyright Holder, or any author named in the components of the |
| 218 | Work, or any other party who may distribute and/or modify the Work as |
| 219 | permitted above, be liable to you for damages, including any general, |
| 220 | special, incidental or consequential damages arising out of any use of |
| 221 | the Work or out of inability to use the Work (including, but not limited |
| 222 | to, loss of data, data being rendered inaccurate, or losses sustained by |
| 223 | anyone as a result of any failure of the Work to operate with any other |
| 224 | programs), even if the Copyright Holder or said author or said other |
| 225 | party has been advised of the possibility of such damages. |
| 226 | |
| 227 | |
| 228 | MAINTENANCE OF THE WORK |
| 229 | ======================= |
| 230 | |
| 231 | The Work has the status `author-maintained' if the Copyright Holder |
| 232 | explicitly and prominently states near the primary copyright notice in |
| 233 | the Work that the Work can only be maintained by the Copyright Holder |
| 234 | or simply that it is `author-maintained'. |
| 235 | |
| 236 | The Work has the status `maintained' if there is a Current Maintainer |
| 237 | who has indicated in the Work that they are willing to receive error |
| 238 | reports for the Work (for example, by supplying a valid e-mail |
| 239 | address). It is not required for the Current Maintainer to acknowledge |
| 240 | or act upon these error reports. |
| 241 | |
| 242 | The Work changes from status `maintained' to `unmaintained' if there |
| 243 | is no Current Maintainer, or the person stated to be Current |
| 244 | Maintainer of the work cannot be reached through the indicated means |
| 245 | of communication for a period of six months, and there are no other |
| 246 | significant signs of active maintenance. |
| 247 | |
| 248 | You can become the Current Maintainer of the Work by agreement with |
| 249 | any existing Current Maintainer to take over this role. |
| 250 | |
| 251 | If the Work is unmaintained, you can become the Current Maintainer of |
| 252 | the Work through the following steps: |
| 253 | |
| 254 | 1. Make a reasonable attempt to trace the Current Maintainer (and |
| 255 | the Copyright Holder, if the two differ) through the means of |
| 256 | an Internet or similar search. |
| 257 | |
| 258 | 2. If this search is successful, then enquire whether the Work |
| 259 | is still maintained. |
| 260 | |
| 261 | a. If it is being maintained, then ask the Current Maintainer |
| 262 | to update their communication data within one month. |
| 263 | |
| 264 | b. If the search is unsuccessful or no action to resume active |
| 265 | maintenance is taken by the Current Maintainer, then announce |
| 266 | within the pertinent community your intention to take over |
| 267 | maintenance. (If the Work is a LaTeX work, this could be |
| 268 | done, for example, by posting to comp.text.tex.) |
| 269 | |
| 270 | 3a. If the Current Maintainer is reachable and agrees to pass |
| 271 | maintenance of the Work to you, then this takes effect |
| 272 | immediately upon announcement. |
| 273 | |
| 274 | b. If the Current Maintainer is not reachable and the Copyright |
| 275 | Holder agrees that maintenance of the Work be passed to you, |
| 276 | then this takes effect immediately upon announcement. |
| 277 | |
| 278 | 4. If you make an `intention announcement' as described in 2b. above |
| 279 | and after three months your intention is challenged neither by |
| 280 | the Current Maintainer nor by the Copyright Holder nor by other |
| 281 | people, then you may arrange for the Work to be changed so as |
| 282 | to name you as the (new) Current Maintainer. |
| 283 | |
| 284 | 5. If the previously unreachable Current Maintainer becomes |
| 285 | reachable once more within three months of a change completed |
| 286 | under the terms of 3b) or 4), then that Current Maintainer must |
| 287 | become or remain the Current Maintainer upon request provided |
| 288 | they then update their communication data within one month. |
| 289 | |
| 290 | A change in the Current Maintainer does not, of itself, alter the fact |
| 291 | that the Work is distributed under the LPPL license. |
| 292 | |
| 293 | If you become the Current Maintainer of the Work, you should |
| 294 | immediately provide, within the Work, a prominent and unambiguous |
| 295 | statement of your status as Current Maintainer. You should also |
| 296 | announce your new status to the same pertinent community as |
| 297 | in 2b) above. |
| 298 | |
| 299 | |
| 300 | WHETHER AND HOW TO DISTRIBUTE WORKS UNDER THIS LICENSE |
| 301 | ====================================================== |
| 302 | |
| 303 | This section contains important instructions, examples, and |
| 304 | recommendations for authors who are considering distributing their |
| 305 | works under this license. These authors are addressed as `you' in |
| 306 | this section. |
| 307 | |
| 308 | Choosing This License or Another License |
| 309 | ---------------------------------------- |
| 310 | |
| 311 | If for any part of your work you want or need to use *distribution* |
| 312 | conditions that differ significantly from those in this license, then |
| 313 | do not refer to this license anywhere in your work but, instead, |
| 314 | distribute your work under a different license. You may use the text |
| 315 | of this license as a model for your own license, but your license |
| 316 | should not refer to the LPPL or otherwise give the impression that |
| 317 | your work is distributed under the LPPL. |
| 318 | |
| 319 | The document `modguide.tex' in the base LaTeX distribution explains |
| 320 | the motivation behind the conditions of this license. It explains, |
| 321 | for example, why distributing LaTeX under the GNU General Public |
| 322 | License (GPL) was considered inappropriate. Even if your work is |
| 323 | unrelated to LaTeX, the discussion in `modguide.tex' may still be |
| 324 | relevant, and authors intending to distribute their works under any |
| 325 | license are encouraged to read it. |
| 326 | |
| 327 | A Recommendation on Modification Without Distribution |
| 328 | ----------------------------------------------------- |
| 329 | |
| 330 | It is wise never to modify a component of the Work, even for your own |
| 331 | personal use, without also meeting the above conditions for |
| 332 | distributing the modified component. While you might intend that such |
| 333 | modifications will never be distributed, often this will happen by |
| 334 | accident -- you may forget that you have modified that component; or |
| 335 | it may not occur to you when allowing others to access the modified |
| 336 | version that you are thus distributing it and violating the conditions |
| 337 | of this license in ways that could have legal implications and, worse, |
| 338 | cause problems for the community. It is therefore usually in your |
| 339 | best interest to keep your copy of the Work identical with the public |
| 340 | one. Many works provide ways to control the behavior of that work |
| 341 | without altering any of its licensed components. |
| 342 | |
| 343 | How to Use This License |
| 344 | ----------------------- |
| 345 | |
| 346 | To use this license, place in each of the components of your work both |
| 347 | an explicit copyright notice including your name and the year the work |
| 348 | was authored and/or last substantially modified. Include also a |
| 349 | statement that the distribution and/or modification of that |
| 350 | component is constrained by the conditions in this license. |
| 351 | |
| 352 | Here is an example of such a notice and statement: |
| 353 | |
| 354 | %% pig.dtx |
| 355 | %% Copyright 2005 M. Y. Name |
| 356 | % |
| 357 | % This work may be distributed and/or modified under the |
| 358 | % conditions of the LaTeX Project Public License, either version 1.3 |
| 359 | % of this license or (at your option) any later version. |
| 360 | % The latest version of this license is in |
| 361 | % http://www.latex-project.org/lppl.txt |
| 362 | % and version 1.3 or later is part of all distributions of LaTeX |
| 363 | % version 2005/12/01 or later. |
| 364 | % |
| 365 | % This work has the LPPL maintenance status `maintained'. |
| 366 | % |
| 367 | % The Current Maintainer of this work is M. Y. Name. |
| 368 | % |
| 369 | % This work consists of the files pig.dtx and pig.ins |
| 370 | % and the derived file pig.sty. |
| 371 | |
| 372 | Given such a notice and statement in a file, the conditions |
| 373 | given in this license document would apply, with the `Work' referring |
| 374 | to the three files `pig.dtx', `pig.ins', and `pig.sty' (the last being |
| 375 | generated from `pig.dtx' using `pig.ins'), the `Base Interpreter' |
| 376 | referring to any `LaTeX-Format', and both `Copyright Holder' and |
| 377 | `Current Maintainer' referring to the person `M. Y. Name'. |
| 378 | |
| 379 | If you do not want the Maintenance section of LPPL to apply to your |
| 380 | Work, change `maintained' above into `author-maintained'. |
| 381 | However, we recommend that you use `maintained', as the Maintenance |
| 382 | section was added in order to ensure that your Work remains useful to |
| 383 | the community even when you can no longer maintain and support it |
| 384 | yourself. |
| 385 | |
| 386 | Derived Works That Are Not Replacements |
| 387 | --------------------------------------- |
| 388 | |
| 389 | Several clauses of the LPPL specify means to provide reliability and |
| 390 | stability for the user community. They therefore concern themselves |
| 391 | with the case that a Derived Work is intended to be used as a |
| 392 | (compatible or incompatible) replacement of the original Work. If |
| 393 | this is not the case (e.g., if a few lines of code are reused for a |
| 394 | completely different task), then clauses 6b and 6d shall not apply. |
| 395 | |
| 396 | |
| 397 | Important Recommendations |
| 398 | ------------------------- |
| 399 | |
| 400 | Defining What Constitutes the Work |
| 401 | |
| 402 | The LPPL requires that distributions of the Work contain all the |
| 403 | files of the Work. It is therefore important that you provide a |
| 404 | way for the licensee to determine which files constitute the Work. |
| 405 | This could, for example, be achieved by explicitly listing all the |
| 406 | files of the Work near the copyright notice of each file or by |
| 407 | using a line such as: |
| 408 | |
| 409 | % This work consists of all files listed in manifest.txt. |
| 410 | |
| 411 | in that place. In the absence of an unequivocal list it might be |
| 412 | impossible for the licensee to determine what is considered by you |
| 413 | to comprise the Work and, in such a case, the licensee would be |
| 414 | entitled to make reasonable conjectures as to which files comprise |
| 415 | the Work. |
| 416 | |