1 Copyright (C) 2007-2014 Free Software Foundation, Inc.
2 See the end of the file for license conditions.
5 NOTES ON COPYRIGHTS AND LICENSES
9 A "copyright notice" consists of one or a few lines of this format:
10 "Copyright (C) 2006, 2007 Free Software Foundation, Inc."
12 A "license notice" is a statement of permissions, and is usually much
13 longer, eg the text "GNU Emacs is free software...".
16 Summary for the impatient:
18 1. Don't add code to Emacs written by someone other than yourself
19 without thinking about the legal aspect. Even if the changes are
20 trivial, consider if they combine with previous changes by the same
21 author to make a non-trivial total. If so, make sure they have an
22 assignment. If adding a whole file adjust the copyright statements in
25 2. When installing code written by someone else, the ChangeLog entry
26 should be in the name of the author of the code, not the person who
27 installs it. Also use bzr commit's "--author" option.
28 Do not install any of your own changes in the same commit.
30 3. With images, add the legal info to a README file in the directory
33 4. If you add a lot of text to a previously trivial file that had no
34 legal notices, consider if you should add a copyright statement.
36 5. Please don't just add an FSF copyright without checking that is the
40 Every non-trivial file distributed through the Emacs repository should be
41 self-explanatory in terms of copyright and license. This includes
42 files that are not distributed in Emacs releases (for example, the
43 admin/ directory), because the whole Emacs repository is publicly
46 The definition of triviality is a little vague, but a rule of thumb is
47 that any file with less than 15 lines of actual content is trivial. If
48 a file is auto-generated (eg ldefs-boot.el) from another one in the
49 repository, then it does not really matter about adding a copyright
50 statement to the generated file.
52 Legal advice says that we could, if we wished, put a license notice
53 even in trivial files, because copyright law in general looks at the
54 overall work as a whole. It is not _necessary_ to do so, and rms
55 prefers that we do not. This means one needs to take care that trivial
56 files do not grow and become non-trivial without having a license
57 added. NB consequently, if you add a lot of text to a small file,
58 consider whether your changes have made the file worthy of a copyright
59 notice, and if so, please add one.
61 It can be helpful to put a reminder comment at the start of a trivial
62 file, eg: "add a license notice if this grows to > 10 lines of code".
64 The years in the copyright notice should be updated every year (see
65 file "years" in this directory). The PDF versions of refcards etc
66 should display copyright notices (an exception to the rule about
67 "generated" files), but these can just display the latest year. The
68 full list of years should be kept in comments in the source file. If
69 these are distributed in the repository, check in a regenerated
70 version when the tex files are updated.
72 Copyright changes should be propagated to any associated repositories
73 (eg Gnus, MH-E), but I think in every case this happens automatically
76 All README (and other such text files) that are non-trivial should
77 contain copyright statements and GPL license notices, exactly as .el
78 files do (see e.g. README in the top-level directory). Before 2007,
79 we used a simple, short statement permitting copying and modification
80 provided legal notices were retained. In Feb 2007 we switched to the
81 standard GPL text, on legal advice. Some older text files in etc/
82 should, however, keep their current licenses (see below for list).
84 For image files, the copyright and license details should be recorded
85 in a README file in each directory with images. (Legal advice says
86 that we need not add notices to each image file individually, if they
87 allow for that.). It is recommended to use the word "convert" to
88 describe the automatic process of changing an image from one format to
89 another (http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00618.html).
92 When installing a file with an "unusual" license (after checking first
93 it is ok), put a copy of the copyright and license in the file (if
94 possible. It's ok if this makes the file incompatible with its
95 original format, if it can still be used by Emacs), or in a README
96 file in the relevant directory.
98 The vast majority of files are copyright FSF and distributed under the
99 GPL. A few files (mainly related to language and charset support) are
100 copyright AIST alone, or both AIST and FSF. (Contact Kenichi Handa
101 with questions about legal issues in such files.) In all these cases,
102 the copyright years in each file should be updated each year.
104 There are some exceptions to the points in the previous paragraph, and
105 these are listed below for reference, together with any files where
106 the copyright needs to be updated in "unusual" ways.
108 If you find any other such cases, please consult to check they are ok,
109 and note them in this file. This includes missing copyright notices,
110 and "odd" copyright holders. In most cases, individual authors should
111 not appear in copyright statements. Either the copyright has been
112 assigned (check copyright.list) to the FSF (in which case the original
113 author should be removed and the year(s) transferred to the FSF); or
114 else it is possible the file should not be in Emacs at all (please
117 Note that it seems painfully clear that one cannot rely on commit logs,
118 or even ChangeLogs, for older changes. People often installed changes
119 from others, without recording the true authorship.
121 [For reference, most of these points were established via email with
122 rms, 2007/1, "Copyright years".
124 In March 2011, information on some files no longer included was removed.
125 Consult older versions of this document if interested.]
128 lisp/version.el # emacs-copyright
129 lib-src/ebrowse.c # version
130 lib-src/etags.c # print_version
131 lib-src/rcs2log # Copyright
132 Cocoa/Emacs.base/Contents/Info.plist
133 Cocoa/Emacs.base/Contents/Resources/English.lproj/InfoPlist.strings
134 GNUstep/Emacs.base/Resources/Info-gnustep.plist
135 `set-copyright' in admin.el will do all the above.
140 - These files are copyright FSF, with unlimited permission to copy,
141 distribute and modify, so long as the copyright notice is preserved.
142 Exception: m4/pkg.m4 is copyright Scott James Remnant; it is
143 distributed under the same terms as for the rest of Emacs.
146 - copyright FSF, with MIT-like license
149 - this file is copyright MIT, which is OK. Leave the copyright alone.
152 also update the \def\year macro for the latest year.
155 - doesn't need a humorless disclaimer, because Karl Fogel says we
156 can consider it part of Emacs, and he has a blanker disclaimer for
157 Emacs changes. (email to rgm "[Emacs-commit] emacs/etc future-bug",
160 etc/letter.pbm,letter.xpm
161 - trivial, no notice needed.
162 <http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00324.html>
165 - trivial (at time of writing), no license needed
168 standard notices. Just a note that although the file itself is not
169 really copyrightable, in the wider context of it being part of
170 Emacs (and written by those with assignments), a standard notice is
174 rms: simple license is fine for this file
176 leim/CXTERM-DIC/4Corner.tit, ARRAY30.tit, CCDOSPY.tit, ECDICT.tit,
177 ETZY.tit, PY-b5.tit, Punct-b5.tit, Punct.tit, QJ-b5.tit, QJ.tit,
178 SW.tit, TONEPY.tit, ZOZY.tit
179 - leave the copyrights alone.
181 leim/MISC-DIC/CTLau-b5.html, CTLau.html, cangjie-table.b5, cangjie-table.cns,
182 pinyin.map, ziranma.cin
183 - leave the copyright alone.
184 Note that pinyin.map, ziranma.cin (and hence the generated
185 leim/quail/PY.el, ZIRANMA.el) are under GPLv1 or later.
187 leim/SKK-DIC/SKK-JISYO.L
189 (the latter is auto-generated from the former). Leave the copyright alone.
192 Copyright information is duplicated in etc/ETAGS.README. Update that
195 Until 2007 etags.c was described as being copyright FSF and Ken Arnold.
196 After some investigation in Feb 2007, then to the best of our
197 knowledge we believe that the original 1984 Emacs version was based
198 on the version in BSD4.2. See for example this 1985 post from Ken Arnold:
199 <http://groups.google.com/group/mod.sources/browse_thread/thread/ffe5c55845a640a9>
200 I have received enough requests for the current source to ctags
201 to post it. Here is the latest version (what will go out with
202 4.3, modulo any bugs fixed during the beta period). It is the
203 4.2 ctags with recognition of yacc and lex tags added.
205 See also a 1984 version of ctags (no copyright) posted to net.sources:
206 <http://groups.google.com/group/net.sources/msg/a21b6c21be12a98d>
207 Version of etags.c in emacs-16.56 duplicates comment typos.
209 Accordingly, in Feb 2007 we added a 1984 copyright for the
210 University of California and a revised BSD license. The terms of
211 this require that the full license details be available in binary
212 distributions - hence the file etc/ETAGS.README. The fact that the
213 --version output just says "Copyright <year> FSF" is apparently OK
214 from a legal point of view.
216 lisp/cedet/semantic/imenu.el
217 - See http://lists.gnu.org/archive/html/emacs-devel/2010-03/msg00410.html
218 in which Eric Ludlam established that the remaining contributions
219 from authors other than himself were negligible.
222 - no special rules about the copyright. We note here that we believe
223 (2007/1) there is no problem with our use of the name "tetris" or
225 rms: "My understanding is that game rules as such are not copyrightable."
226 <http://lists.gnu.org/archive/html/emacs-devel/2007-01/msg00960.html>
227 rms: Legal advice is that we are ok and need not worry about this.
231 - there are also copyrights in the body of the file. Update these too.
235 rms (2007/02/17): "lwlib is not assigned to the FSF; we don't consider
236 it part of Emacs. [...] Therefore non-FSF copyrights are ok in lwlib."
238 NB don't change the GPL version used for lwlib .c and .h files (see
241 FSF copyrights should only appear in files which have undergone
242 non-trivial cumulative changes from the original versions in the Lucid
243 Widget Library. NB this means that if you make non-trivial changes to
244 a file with no FSF copyright, you should add one. Also, if changes are
245 reverted to the extent that a file becomes basically the same as the
246 original version, the FSF copyright should be removed.
248 In my (rgm) opinion, as of Feb 2007, all the non-trivial files differ
249 significantly from the original versions, with the exception of
250 lwlib-Xm.h. Most of the changes that were made to this file have
251 subsequently been reverted. Therefore I removed the FSF copyright from
252 this file (which is arguably too trivial to merit a notice anyway). I
253 added FSF copyright to the following files which did not have them
254 already: Makefile.in, lwlib-Xaw.c, lwlib-int.h (borderline),
255 lwlib-utils.c (borderline), lwlib.c, lwlib.h.
257 Copyright years before the advent of public CVS in 2001 were those
258 when I judged (from the CVS logs) that non-trivial amounts of change
259 had taken place. I also adjusted the existing FSF years in xlwmenu.c,
260 xlwmenu.h, and xlwmenuP.h on the same basis.
262 Note that until Feb 2007, the following files in lwlib were lacking
263 notices: lwlib-int.h, lwlib.h, lwlib-Xaw.h, lwlib-Xlw.h, lwlib-utils.h
265 The following files did not list a Lucid copyright: xlwmenu.h,
268 To the best of our knowledge, all the code files in lwlib were
269 originally part of the Lucid Widget Library, even if they did not say
270 so explicitly. For example, they were all present in Lucid Emacs 19.1
271 in 1992. The exceptions are the two Xaw files, which did not appear
272 till Lucid Emacs 19.9 in 1994. The file lwlib-Xaw.h is too trivial to
273 merit a copyright notice, but would presumably have the same one as
274 lwlib-Xaw.c. We have been unable to find a true standalone version of
275 LWL, if there was such a thing, to check definitively.
277 To clarify the situation, in Feb 2007 we added Lucid copyrights and
278 GPL notices to those files lacking either that were non-trivial,
279 namely: lwlib-int.h, lwlib.h, xlwmenu.h, xlwmenuP.h. This represents
280 our best understanding of the legal status of these files. We also
281 clarified the notices in Makefile.in, which was originally the
282 Makefile auto-generated from Lucid's Imakefile.
284 As of Feb 2007, the following files are considered too trivial for
285 notices: lwlib-Xaw.h, lwlib-Xlw.h, lwlib-utils.h.
287 The version of lwlib/ first installed in Emacs seems to be the same as
288 that used in Lucid Emacs 19.8 (released 6-sep-93); except the two Xaw
289 files, which did not appear till Athena support was added in Lucid
290 Emacs 19.9. In Lucid Emacs 19.1, all files were under GPLv1 or later,
291 but by Lucid Emacs 19.8, lwlib.c and xlwmenu.c had been switched to v2
292 or later. These are the versions that were first installed in Emacs.
293 So in GNU Emacs, these two files have been under v2 or later since
296 It seems that it was the intention of Lucid to use v1 or later
297 (excepting the two files mentioned previously); so this is the license
298 we have used when adding notices to code that did not have notices
299 originally. Although we have the legal right to switch to v2 or later,
300 rms prefers that we do not do so.
303 doc/*/doclicense.texi
304 - leave the copyright alone in this imported file.
306 doc/*/*.texi - All manuals should be under GFDL (but see below), and
307 should include a copy of it, so that they can be distributed
308 separately. faq.texi has a different license, for some reason no-one
310 http://lists.gnu.org/archive/html/emacs-devel/2007-04/msg00583.html
311 http://lists.gnu.org/archive/html/emacs-devel/2007-04/msg00618.html
313 doc/misc/mh-e.texi is dual-licensed (GPL and GFDL) per agreement with
314 FSF (reconfirmed by rms Aug 25 2008). Discussion with
315 licensing@fsf.org starting on Thu, 07 Aug 2003 with subject:
316 "[gnu.org #58812] Changing license of MH-E manual"
319 msdos/is_exec.c, sigaction.c - these files are copyright DJ Delorie.
320 Leave the copyrights alone. Leave the Eli Zaretskii copyright in
321 is_exec.c alone. See the msdos/README file for the legal history of
324 msdos/sed*.inp - These files are copyright FSF and distributed under
329 Keep the "copyright.h" method used by X11, rather than moving the
330 licenses into the files. Note that the original X10.h did not use
331 copyright.h, but had an explicit notice, which we retain.
333 If you make non-trivial changes to a file which does not have an FSF
334 notice, add one and a GPL notice (as per Activate.c). If changes to a
335 file are reverted such that it becomes essentially the same as the
336 original X11 version, remove the FSF notice and GPL.
338 Only the files which differ significantly from the original X11
339 versions should have FSF copyright and GPL notices. At time of writing
340 (Feb 2007), this is: Activate.c, Create.c, Internal.c. I (rgm)
341 established this by diff'ing the current files against those in X11R1,
342 and when I found significant differences looking in the ChangeLog for
343 the years they originated (the CVS logs are truncated before 1999). I
344 therefore removed the FSF notices (added in 200x) from the other
345 files. There are some borderline cases IMO: AddSel.c, InsSel.c,
346 XMakeAssoc.c, XMenu.h. For these I erred on the side of NOT adding FSF
349 With regards to whether the files we have changed should have GPL
350 added or not, rms says (2007-02-25, "oldXmenu issues"):
352 It does not make much difference, because oldXmenu is obsolete
353 except for use in Emacs (and it is not normally used in Emacs any
356 So, to make things simple, please put our changes under the GPL.
358 insque.c had no copyright notice until 2005. The version of insque.c
359 added to Emacs 1992-01-27 is essentially the same as insremque.c added
360 to glic three days later by Roland McGrath, with an FSF copyright and
361 GPL, but no ChangeLog entry:
362 <http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/libc/misc/insremque.c?\
363 rev=1.1&cvsroot=glibc>
364 To the best of his recollection, McGrath (who has a copyright
365 assignment) was the author of this file (email from roland at frob.com
366 to rms, 2007-02-23, "Where did insque.c come from?"). The FSF
367 copyright and GPL in this file are therefore correct as far as we
370 Imakefile had no legal info in Feb 2007, but was obviously based on
371 the X11 version (which also had no explicit legal info). As it was
372 unused, I removed it. It would have the same MIT copyright as
373 Makefile.in does now.
377 - contains numerous copyrights from the GNU C library. Leave them alone.
380 - see comments below. This file is OK to be released with Emacs
381 22, but we may want to revisit it afterwards.
384 ** Some notes on resolved issues, for historical information only
387 rms: "surely written either by me or by ESR. (If you can figure out
388 which year, I can probably tell you which.) Either way, we have papers
389 for it." It was present in Emacs-16.56 (15-jul-85). rms: "Then I
390 conclude it was written by me."
393 - had no copyright notice till Feb 2007. ChangeLog.3 suggests it was
394 written by Eric Raymond. When asked by rms on 14 Feb 2007 he said:
396 I don't remember writing it, but it reads like my prose and I believe
397 I wrote the feature(s) it's describing. So I would have been the
398 likeliest person to write it.
400 Odds are that I did, but I'm not certain.
402 Accordingly, FSF copyright was added.
405 http://lists.gnu.org/archive/html/emacs-devel/2007-02/msg00138.html
406 - briefly removed due to legal uncertainly Jan-Mar 2007. The
407 relevant assignment is under "hp9k800" in copyright.list. File was
408 written by John V. Morris at HP, and disclaimed by the author and
409 HP. So this file is public domain.
412 lisp/progmodes/python.el
413 Dave Love alerted us to a potential legal problem:
414 http://lists.gnu.org/archive/html/emacs-pretest-bug/2007-04/msg00459.html
416 On consultation with a lawyer, we found there was no problem:
417 http://lists.gnu.org/archive/html/emacs-devel/2007-05/msg00466.html
420 ** Issues that are "fixed" for the release of Emacs 22, but we may
421 wish to revisit later in more detail
424 admin/check-doc-strings
425 File says it's in the public domain, but that might not make it so.
429 On legal advice from Matt Norwood, the following comment was added
430 to these files in Feb/Mar 2007:
432 The code here is forced by the interface, and is not subject to
433 copyright, constituting the only possible expression of the
434 algorithm in this format.
436 With the addition of this notice, these files are OK for the
437 upcoming Emacs-22 release. Post-release, we can revisit this issue
438 and possibly add a list of all authors who have changed these files.
439 (details in email from Matt Norwood to rms, 2007/02/03).
441 src/s/aix3-2.h, hpux8.h, hpux9.h, irix5-0.h, netbsd.h, usg5-4-2.h
442 [note some of these have since been merged into other files]
443 - all these (not obviously trivial) files were missing copyrights
444 till Feb 2007, when FSF copyright was added. Matt Norwood advised:
446 For now, I think the best policy is to assume that we do have
447 assignments from the authors (I recall many of these header files
448 as having been originally written by rms), and to attach an FSF
449 copyright with GPL notice. We can amend this if and when we
450 complete the code audit. Any additions to these files by
451 non-assigned authors are arguably "de minimis" contributions to
452 Emacs: small changes or suggestions to a work that are subsumed in
453 the main authors' copyright in the entire work.
455 Here is my (rgm) take on the details of the above files:
458 I would say started non-trivial (1993, jimb, heavily based
459 on irix4-0.h). A few borderline non-tiny changes since.
462 started non-trivial, but was heavily based on usg5-4.h, which was and is
463 copyright FSF. only tiny changes since installed.
465 aix3-2.h, hpux8.h, hpux9.h, netbsd.h
466 started trivial, grown in tiny changes.
469 Roland McGrath said to rms (2007/02/17): "I don't really remember
470 anything about it. If I put it in without other comment, then probably
474 Someone might want to tweak the copyright years (for dates before
475 2001) that I used in all these files.
477 Note: erring on the side of caution, I also added notices to some
478 files I thought might be considered non-trivial (if one includes
480 aix4-1.h hpux10.h irix6-5.h
483 (everything with > 30 non-blank lines, which at least is _some_ kind of
487 *** These are copyright issues that need not be fixed until after
488 Emacs 22 is released (though if they can be fixed before, that is
492 Is it OK to just `bzr remove' a file for legal reasons, or is
493 something more drastic needed? A removed file is still available from
494 the repository, if suitable options are applied. (This issue obviously
495 does not affect a release).
499 Make sure that all files with non-standard copyrights or licenses are
503 REMOVED etc/gnu.xpm, nt/icons/emacs21.ico, nt/icons/sink.ico
504 - Restore if find legal info. emacs21.ico is not due to Davenport.
505 Geoff Voelker checked but could not find a record of where it came
510 Image files from GTK, Gnome are under GPLv2 (no "or later"?). RMS will
511 contact image authors in regards to future switch to v3.
514 etc/TUTORIAL* (translations)
515 switch to GPL (see english TUTORIAL)
516 rms: "We can leave the TUTORIAL translations alone until their
517 maintainers update them."
518 Can adapt short license text from end of GPL translations at:
519 http://www.gnu.org/licenses/translations.html
520 Only a few sentences around the license notice need changing from
525 *** These are copyright issues still to be addressed:
530 ** NOTES ON RELICENSING TO GPL3
532 The EMACS_22_BASE branch was changed to GPLv3 (or later) 2007/07/25.
535 (see http://lists.gnu.org/archive/html/emacs-devel/2007-07/msg01431.html)
537 1. There are some files in the Emacs tree which are not part of Emacs (eg
538 those included from Gnulib). These are all copyright FSF and (at time
539 of writing) GPL >= 2. rms says may as well leave the licenses of these
540 alone (may import them from Gnulib again). These are:
544 build-aux/config.guess
548 build-aux/move-if-change
549 build-aux/snippet/_Noreturn.h
550 build-aux/snippet/arg-nonnull.h
551 build-aux/snippet/c++defs.h
552 build-aux/snippet/warn-on-use.h
560 Note _not_ included in the above are src/regex.{c,h} (rms: "That
561 forked version is only in Emacs, so definitely relicense that."), and
562 oldXMenu/insque.c (rms: "We wrote that specifically for Emacs, so
563 definitely relicense that.").
565 2. The files that are copyright FSF and AIST, or AIST alone, should be
566 and were updated, ditto the oldXMenu files with FSF copyright, and
567 msdos/is_exec.c and sigaction.c.
571 Files originally in Lucid Widget Library were left alone (excludes
572 ChangeLog, etc), ie remain under GPL v1 or later, or v2 or later.
573 (rms: "We may as well leave this alone, since we are never going to
576 4. There are some files where the FSF holds no copyright. These were
579 leim/MISC-DIC/CTLau-b5.html >= v2
580 leim/MISC-DIC/CTLau.html >= v2
581 (above included in lisp/international/titdic-cnv.el)
582 leim/MISC-DIC/pinyin.map >= v1
583 leim/MISC-DIC/ziranma.cin >= v1
584 leim/SKK-DIC/SKK-JISYO.L >= v2
585 leim/SKK-DIC/README >= v2
586 leim/ja-dic/ja-dic.el >= v2
588 5. At time of writing, some non-Emacs icons included from Gnome remain
589 under GPLv2 (no "or later"). See:
591 etc/images/gnus/README
592 etc/images/mail/README
597 This file is part of GNU Emacs.
599 GNU Emacs is free software: you can redistribute it and/or modify
600 it under the terms of the GNU General Public License as published by
601 the Free Software Foundation, either version 3 of the License, or
602 (at your option) any later version.
604 GNU Emacs is distributed in the hope that it will be useful,
605 but WITHOUT ANY WARRANTY; without even the implied warranty of
606 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
607 GNU General Public License for more details.
609 You should have received a copy of the GNU General Public License
610 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.