license, as only those competitors who adopt and comply with the GPLv2's

terms can benefit from the implied patent license. To continue the

example above, Company \compB{} does not receive a free ride on Company

\compA's patent, as Company \compB{} has not licensed-in and then

redistributed Company A's advanced Web browser under the GPLv2. If Company

\compB{} does do that, however, Company \compA{} still has not lost

competitive advantage against Company \compB{}, as Company \compB{} must then,

when it re-distributes Company \compA's program, grant an implied license

to any of its patents that cover the program. Further, if Company \compB{}

relicenses an improved version of Company A's program, it must do so under

the GPLv2, meaning that any patents it holds that cover the improved version

are impliedly licensed to any licensee. As such, the only way Company

\compB{} can benefit from Company \compA's implied patent license, is if it,

itself, distributes Company \compA's software program and grants an

implied patent license to any of its patents that cover that program.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{Defending Freedom on Many Fronts}

Chapters~\ref{run-and-verbatim} and~\ref{source-and-binary} presented the

core freedom-defending provisions of GPLv2\@, which are in GPLv2~\S\S0--3.

GPLv2\S\S~4--7 of the GPLv2 are designed to ensure that GPLv2~\S\S0--3 are

not infringed, are enforceable, are kept to the confines of copyright law but

also  not trumped by other copyright agreements or components of other

entirely separate legal systems.  In short, while GPLv2~\S\S0--3 are the parts

of the license that defend the freedoms of users and programmers,

GPLv2~\S\S4--7 are the parts of the license that keep the playing field clear

so that \S\S 0--3 can do their jobs.

\section{GPLv2~\S4: Termination on Violation}

\label{GPLv2s4}

GPLv2~\S4 is GPLv2's termination clause.  Upon first examination, it seems

strange that a license with the goal of defending users' and programmers'

freedoms for perpetuity in an irrevocable way would have such a clause.

However, upon further examination, the difference between irrevocability

and this termination clause becomes clear.

The GPL is irrevocable in the sense that once a copyright holder grants

rights for someone to copy, modify and redistribute the software under terms

of the GPL, they cannot later revoke that grant.  Since the GPL has no

provision allowing the copyright holder to take such a prerogative, the

license is granted as long as the copyright remains in effect.\footnote{In

  the USA, due to unfortunate legislation, the length of copyright is nearly

  perpetual, even though the Constitution forbids perpetual copyright.} The

copyright holders have the right to relicense the same work under different

licenses (see Section~\ref{Proprietary Relicensing} of this tutorial), or to

stop distributing the GPLv2'd version (assuming GPLv2~\S3(b) was never used),

but they may not revoke the rights under GPLv2 already granted.

In fact, when an entity looses their right to copy, modify and distribute

GPL'd software, it is because of their \emph{own actions}, not that of the

copyright holder.  The copyright holder does not decided when GPLv2~\S4

termination occurs (if ever); rather, the actions of the licensee determine

that.

Under copyright law, the GPL has granted various rights and freedoms to

the licensee to perform specific types of copying, modification, and

redistribution.  By default, all other types of copying, modification, and

redistribution are prohibited.  GPLv2~\S4 says that if you undertake any of

those other types (e.g., redistributing binary-only in violation of GPLv2~\S3),

then all rights under the license --- even those otherwise permitted for

those who have not violated --- terminate automatically.

GPLv2~\S4 makes GPLv2 enforceable.  If licensees fail to adhere to the

license, then they are stuck without any permission under to engage in

activities covered by copyright law.  They must completely cease and desist

from all copying, modification and distribution of the GPL'd software.

At that point, violating licensees must gain the forgiveness of the copyright

holders to have their rights restored.  Alternatively, the violators could

negotiate another agreement, separate from GPL, with the copyright

holder.  Both are common practice, although

\tutorialpartsplit{as discussed in \textit{A Practical Guide to GPL

    Compliance}, there are }{Chapter~\ref{compliance-understanding-whos-enforcing}

  explains further } key differences between these two very different uses of GPL.

\section{GPLv2~\S5: Acceptance, Copyright Style}

\label{GPLv2s5}

GPLv2~\S5 brings us to perhaps the most fundamental misconception and common

confusion about GPLv2\@. Because of the prevalence of proprietary software,

most users, programmers, and lawyers alike tend to be more familiar with

EULAs. EULAs are believed by their authors to be contracts, requiring

formal agreement between the licensee and the software distributor to be

valid. This has led to mechanisms like ``shrink-wrap'' and ``click-wrap''

as mechanisms to perform acceptance ceremonies with EULAs.

The GPL does not need contract law to ``transfer rights.''  Usually, no rights

are transfered between parties.  By contrast, the GPL is primarily a permission

slip to undertake activities that would otherwise have been prohibited

by copyright law.  As such, GPL needs no acceptance ceremony; the

licensee is not even required to accept the license.

However, without the GPL, the activities of copying, modifying and

distributing the software would have otherwise been prohibited.  So, the

GPL says that you only accepted the license by undertaking activities that

you would have otherwise been prohibited without your license under GPL\@.

This is a certainly subtle point, and requires a mindset quite different

from the contractual approach taken by EULA authors.

An interesting side benefit to GPLv2~\S5 is that the bulk of users of Free

Software are not required to accept the license.  Undertaking fair and

unregulated use of the work, for example, does not bind you to the GPL,

since you are not engaging in activity that is otherwise controlled by

copyright law.  Only when you engage in those activities that might have an

impact on the freedom of others does license acceptance occur, and the

terms begin to bind you to fair and equitable sharing of the software.  In

other words, the GPL only kicks in when it needs to for the sake of

freedom.

While GPL is by default a copyright license, it is certainly still possible

to consider GPL as a contract as well.  For example, some distributors chose

to ``wrap'' their software in an acceptance ceremony to GPL, and nothing in

GPL prohibits that use.  Furthermore, the ruling in \textit{Jacobsen

  v. Katzer, 535 F.3d 1373, 1380 (Fed.Cir.2008)} indicates that \textbf{both}

copyright and contractual remedies may be sought by a copyright holder

seeking to enforce a license designed to uphold software freedom.

\section{Using GPL Both as a Contract and Copyright License}

\section{GPLv2~\S6: GPL, My One and Only}

\label{GPLv2s6}

A point that was glossed over in Section~\ref{GPLv2s4}'s discussion of GPLv2~\S4

was the irrevocable nature of the GPL\@. The GPLv2 is indeed irrevocable,

and it is made so formally by GPLv2~\S6.

The first sentence in GPLv2~\S6 ensures that as software propagates down the

distribution chain, that each licensor can pass along the license to each

new licensee.  Under GPLv2~\S6, the act of distributing automatically grants a

license from the original licensor to the next recipient.  This creates a

chain of grants that ensure that everyone in the distribution has rights

under the GPLv2\@.  In a mathematical sense, this bounds the bottom ---

making sure that future licensees get no fewer rights than the licensee before.

The second sentence of GPLv2~\S6 does the opposite; it bounds from the top.  It

prohibits any licensor along the distribution chain from placing

additional restrictions on the user.  In other words, no additional

requirements may trump the rights and freedoms given by GPLv2\@.

The final sentence of GPLv2~\S6 makes it abundantly clear that no individual

entity in the distribution chain is responsible for the compliance of any

other.  This is particularly important for noncommercial users who have

passed along a source offer under GPLv2~\S3(c), as they cannot be assured that

the issuer of the offer will honor their GPLv2~\S3 obligations.

In short, GPLv2~\S6 says that your license for the software is your one and

only copyright license allowing you to copy, modify and distribute the

software.

\section{GPLv2~\S7: ``Give Software Liberty or Give It Death!''}

\label{GPLv2s7}

In essence, GPLv2~\S7 is a verbosely worded way of saying for non-copyright

systems what GPLv2~\S6 says for copyright.  If there exists any reason that a

distributor knows of that would prohibit later licensees from exercising

their full rights under GPL, then distribution is prohibited.

Originally, this was designed as the title of this section suggests --- as

a last ditch effort to make sure that freedom was upheld.  However, in

modern times, it has come to give much more.  Now that the body of GPL'd

software is so large, patent holders who would want to be distributors of

GPL'd software have a tough choice.  They must choose between avoiding

distribution of GPL'd software that exercises the teachings of their

patents, or grant a royalty-free, irrevocable, non-exclusive license to

those patents.  Many companies have chosen the latter.

Thus, GPLv2~\S7 rarely gives software death by stopping its distribution.

Instead, it is inspiring patent holders to share their patents in the same

freedom-defending way that they share their copyrighted works.

\section{GPLv2~\S8: Excluding Problematic Jurisdictions}

\label{GPLv2s8}

GPLv2~\S8 is rarely used by copyright holders.  Its intention is that if a

particular country, say Unfreedonia, grants particular patents or allows

copyrighted interfaces (no country to our knowledge even permits those

yet), that the GPLv2'd software can continue in free and unabated

distribution in the countries where such controls do not exist.

As far as is currently known, GPLv2~\S8 has never been formally used by any

copyright holders.  Some have used GPLv2~\S8 to explain various odd special

topics of distribution, but generally speaking, this section is not

particularly useful and was actually removed in GPLv3.

% FIXME: integrate this into this section.

To our knowledge, no one has invoked this section to add an explicit

geographical distribution limitation since GPLv2 was released in 1991. We

have concluded that this provision is not needed and is not expected to be

needed in the future, and that it therefore should be removed.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{Odds, Ends, and Absolutely No Warranty}

GPLv2~\S\S0--7 constitute the freedom-defending terms of the GPLv2.  The remainder

of the GPLv2 handles administrivia and issues concerning warranties and

liability.

\section{GPLv2~\S9: FSF as Stewards of GPL}

\label{GPLv2s9}

FSF reserves the exclusive right to publish future versions of the GPL\@;

GPLv2~\S9 expresses this.  While the stewardship of the copyrights on the body

of GPL'd software around the world is shared among thousands of

individuals and organizations, the license itself needs a single steward.

Forking of the code is often regrettable but basically innocuous.  Forking

of licensing is disastrous.

(Chapter~\ref{tale-of-two-copylefts} discusses more about the various

versions of GPL.)

\section{GPLv2~\S10: Relicensing Permitted}

\label{GPLv2s10}

GPLv2~\S10 reminds the licensee of what is already implied by the nature of

copyright law.  Namely, the copyright holder of a particular software

program has the prerogative to grant alternative agreements under separate

copyright licenses.

\section{GPLv2~\S11: No Warranty}

\label{GPLv2s11}

Most warranty disclaimer language shout at you.  The

\href{http://www.law.cornell.edu/ucc/2/2-316}{Uniform Commercial

  Code~\S2-316} requires that disclaimers of warranty be ``conspicuous''.

There is apparently general acceptance that \textsc{all caps} is the

preferred way to make something conspicuous, and that has over decades worked

its way into the voodoo tradition of warranty disclaimer writing.

Some have argued the GPL is unenforceable in some jurisdictions because

its disclaimer of warranties is impermissibly broad.  However, GPLv2~\S11

contains a jurisdictional savings provision, which states that it is to be

interpreted only as broadly as allowed by applicable law.  Such a

provision ensures that both it, and the entire GPL, is enforceable in any

jurisdiction, regardless of any particular law regarding the

permissibility of certain warranty disclaimers.

Finally, one important point to remember when reading GPLv2~\S11 is that GPLv2~\S1

permits the sale of warranty as an additional service, which GPLv2~\S11 affirms.

\section{GPLv2~\S12: Limitation of Liability}

\label{GPLv2s12}

There are many types of warranties, and in some jurisdictions some of them

cannot be disclaimed.  Therefore, usually agreements will have both a

warranty disclaimer and a limitation of liability, as we have in GPLv2~\S12.

GPLv2~\S11 thus gets rid of all implied warranties that can legally be

disavowed. GPLv2~\S12, in turn, limits the liability of the actor for any

warranties that cannot legally be disclaimed in a particular jurisdiction.

Again, some have argued the GPL is unenforceable in some jurisdictions

because its limitation of liability is impermissibly broad. However, \S

12, just like its sister, GPLv2~\S11, contains a jurisdictional savings

provision, which states that it is to be interpreted only as broadly as

allowed by applicable law.  As stated above, such a provision ensures that

both GPLv2~\S12, and the entire GPL, is enforceable in any jurisdiction,

regardless of any particular law regarding the permissibility of limiting

liability.

So end the terms and conditions of the GNU General Public License.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{GPLv3}

\label{GPLv3}

This chapter discussed the text of GPLv3.  Much of this material herein

includes text that was adapted (with permission) from text that FSF

originally published as part of the so-called ``rationale documents'' for the

various discussion drafts of GPLv3.

The FSF ran a somewhat public process to develop GPLv3, and it was the first

attempt of its kind to develop a Free Software license this way.  Ultimately,

RMS was the primary author of GPLv3, but he listened to feedback from all

sorts of individuals and even for-profit companies.  Nevertheless, in

attempting to understand GPLv3 after the fact, the materials available from

the GPLv3 process have a somewhat ``drinking from the firehose'' effect.

This chapter seeks to explain GPLv3 to newcomers, who perhaps are familiar

with GPLv2.

\section{Understanding GPLv3 As An Upgraded GPLv2}

Ultimately, GPLv2 and GPLv3 co-exist as active licenses in regular use.  As

discussed in Chapter\~ref{tale-of-two-copylefts}, GPLv1 was never in regular

use alongside GPLv2.  However, given GPLv2's widespread popularity and

existing longevity by the time GPLv3 was published, it is not surprising that

some licensors have continued to prefer GPLv2-only or GPLv2-or-later as their

preferred license.  GPLv3 has gained major adoption by many projects, old and

new, but many projects have not upgraded due to (in some cases) mere laziness

and (in other cases) policy preference for some of GPLv2's terms.

Given this ``two GPLs'' world is the one we all live in, it makes sense to

consider GPLv3 in terms of how it differs from GPLv2.  Also, most of the best

GPL experts in the world must deal regularly with both licenses, and

admittedly have decades of experience of GPLv2 while the most experience with

GPLv3 that's possible is by default less than a decade.

These two factors usually cause even new students of GPL to start with GPLv2

and move on to GPLv3, and this tutorial follows that pattern.

Overall, the changes made in GPLv3 admittedly \textit{increased} the

complexity of the license.  The FSF stated at the start of the GPLv3 process

that they would have liked to oblige those who have asked for a simpler and

shorter GPL\@.  Ultimately, the FSF gave priority to making GPLv3 do the job

that needs to be done to build a better copyleft.  Obsession for concision

should never trump software freedom.

\section{GPLv3~\S0: Giving In On ``Defined Terms''}

One of lawyers' most common complaints about GPLv2 is that defined terms in

the document appear throughout.  Most licenses define terms up-front.

However, GPL was always designed both as a document that should be easily

understood both by lawyers and by software developers: it is a document

designed to give freedom to software developers and users, and therefore it

should be comprehensible to that constituency.

Interestingly enough, one coauthor of this tutorial who is both a lawyer and

a developer pointed out that in law school, she understood defined terms more

quickly than other law students precisely because of her programming

background.  For developers, having \verb0#define0 (in the C programming

language) or other types of constants and/or macros that automatically expand

in the place where they are used is second nature.  As such, adding a defined

terms section was not terribly problematic for developers, and thus GPLv3

adds one.  Most of these defined terms are somewhat straightforward and bring

forward better worded definitions from GPLv2.  Herein, this tutorial

discusses a few of the new ones.

GPLv3~\S0 includes definitions of four new terms not found in any form in

GPLv2: ``covered work'', ``propagate'', ``convey'', and ``Appropriate Legal

Notices''.

While ``covered by this license'' is a phrase found in GPLv2, defining it

more complete in a single as ``covered work'' enables some of the wording in

GPLv3 to be simpler and clearer than its GPLv2 counterparts.

% FIXME: does propagate  definition still work the same way in final draft?

The term ``propagate'' serves two purposes.  First, ``propagate'' provides a

simple and convenient means for distinguishing between the kinds of uses of a

work that the GPL imposes conditions on and the kinds of uses that the GPL

does not (for the most part) impose conditions on.

Second, ``propagate'' furthers our goal of making the license as global as

possible in its wording and effect.  When a work is licensed under the GPL,

the copyright law of some particular country will govern certain legal issues

arising under the license.  A term like ``distribute'' or its equivalent in

languages other than English, is used in several national copyright statutes.

The scope of ``distribution'' in the copyright context can differ from

country to country.  The GPL does not seek to necessarily use the specific

meaning of ``distribution'' that exists under United States copyright law or

any other country's copyright law.

Therefore, the GPL defines the term ``propagate'' by reference to activities

that require permission under ``applicable copyright law'', but excludes

execution and private modification from the definition.  GPLv3's definition

also gives examples of activities that may be included within ``propagation''

but it also makes clear that, under the copyright laws of a given country,

``propagation'' may include other activities as well.

% FIXME: paragraph number change , and more on Convey once definition comes.

The third paragraph of section 2 represents another effort to compensate for

variation in national copyright law.  We distinguish between propagation that

enables parties other than the licensee to make or receive copies, and other

forms of propagation.  As noted above, the meaning of ``distribution'' under

copyright law varies from country to country, including with respect to

whether making copies available to other parties (such as related public or

corporate entities) is ``distribution.'' ``Propagation,'' however, is a term

not tied to any statutory language.  Propagation that does not enable other

parties to make or receive copies --- for example, making private copies or

privately viewing the program --- is permitted unconditionally.  Propagation

that does enable other parties to make or receive copies is permitted as

``distribution,'' subject to the conditions set forth in sections 4--6.

% FIXME: Appropriate Legal Notices

\section{GPLv3~\S1: Understanding CCS}

% FIXME: Talk briefly about importance of CCS and reference compliance guide

% FIXME: reword source code a bit

% FIXME: CCS Coresponding Source updated to newer definition in later drafts

Keeping with the desire to ``round up'' definitions that were spread

throughout the text of GPLv2, the definition of CCS\footnote{Note that the

  preferred term by those who work with both GPLv2 and GPLv3 is ``Complete

  Corresponding Source'', abbreviated to ``CCS''.  Admittedly, the word

  ``complete'' no longer appears in GPLv3 (which uses the word ``all''

  instead).  However, both GPLv2 and the early drafts of GPLv3 itself used

  the word complete, and early GPLv3 drafts even included the phrase

  ``Complete Corresponding Source''.  Meanwhile, use of the acronym ``CCS''

  (sometimes, ``C&CS'') was so widespread among GPL enforcers that its use

  continues even though GPLv3-focused experts tend to say just the defined

  term of ``Corresponding Source''.}, or, as GPLv3 officially calls it,

``Corresponding Source'', is given in GPLv3~\S1\P4.  This definition is as

broad as necessary to protect users' exercise of their rights under the

GPL. We follow the definition with particular examples to remove any doubt

that they are to be considered Complete Corresponding Source Code. We wish to

make completely clear that a licensee cannot avoid complying with the

requirements of the GPL by dynamically linking an add-on component to the

original version of a program.

Though the definition of Complete Corresponding Source Code in the

second paragraph of section 1 is expansive, it is not sufficient to

protect users' freedoms in many circumstances.  For example, a GPL'd

program, or a modified version of such a program, might need to be

signed with a key or authorized with a code in order for it to run on

a particular machine and function properly. Similarly, a program that

produces digitally-restricted files might require a decryption code in

order to read the output.  

% FIXME: Standard Interface

% FIXME: System Libraries: it's in a different place and changed in later drafts

The final paragraph of section 1 revises the exception to the source code

distribution requirement in GPLv2 that we have sometimes called the system

library exception. This exception has been read to prohibit certain

distribution arrangements that we consider reasonable and have not sought to

prevent, such as distribution of gcc linked with a non-free C library that is

included as part of a larger non-free system. This is not to say that such

non-free libraries are legitimate; rather, preventing free software from

linking with these libraries would hurt free software more than it would hurt

proprietary software.

As revised, the exception has two parts. Part (a) rewords the GPLv2

exception for clarity but also removes the words ``unless that

component itself accompanies the executable.''  By itself, (a) would

be too permissive, allowing distributors to evade their

responsibilities under the GPL.  We have therefore added part (b) to

specify when a system library that is an adjunct of a major essential

operating system component, compiler, or interpreter does not trigger

the requirement to distribute source code.  The more low-level the

functionality provided by the library, the more likely it is to be

qualified for this exception.

\section{GPLv3~\S2: Basic Permissions}

% FIXME: phrase ``unmodified Program'' appears due to User Products exception

We have included the first sentence of section 2 to further internationalize

the GPL. Under the copyright laws of some countries, it may be necessary for

a copyright license to include an explicit provision setting forth the

duration of the rights being granted. In other countries, including the

United States, such a provision is unnecessary but permissible.

The first paragraph of section 2 also acknowledges that licensees under the

GPL enjoy rights of copyright fair use, or the equivalent under applicable

law. These rights are compatible with, and not in conflict with, the freedoms

that the GPL seeks to protect, and the GPL cannot and should not restrict

them.

% FIXME: propagate and convey

Section 2 distinguishes between activities of a licensee that are permitted

without limitation and activities that trigger additional requirements. The

second paragraph of section 2 guarantees the basic freedoms of privately

modifying and running the program. However, the right to privately modify and

run the program is terminated if the licensee brings a patent infringement

lawsuit against anyone for activities relating to a work based on the

program.

\section{GPLv3~\S3: What Hath DMCA Wrought}

\label{GPLv3s3}

% FIXME: reference the section in DMCA about this, maybe already there in

%        GPLv2 section?

% FIXME: Wrong paragraph now.

The second paragraph of section 3 declares that no GPL'd program is part of

an effective technological protection measure, regardless of what the program

does. Ill-advised legislation in the United States and other countries has

prohibited circumvention of such technological measures. If a covered work is

distributed as part of a system for generating or accessing certain data, the

effect of this paragraph is to prevent someone from claiming that some other

GPL'd program that accesses the same data is an illegal circumvention.

\section{GPLv3~\S4: Verbatim Copying}

% FIXME: there appear to be minor changes here in later drafts, fix that.

Section 4 has been revised from its corresponding section in GPLv2 in light

of the new section 7 on license compatibility. A distributor of verbatim

copies of the program's source code must obey any existing additional terms

that apply to parts of the program. In addition, the distributor is required

to keep intact all license notices, including notices of such additional

terms.

\section{GPLv3~\S5: Modified Source}

% FIXME: 5(a) is slightly different in final version

Section 5 contains a number of changes relative to the corresponding section

in GPLv2. Subsection 5a slightly relaxes the requirements regarding notice of

changes to the program. In particular, the modified files themselves need no

longer be marked. This reduces administrative burdens for developers of

modified versions of GPL'd software.

Under subsection 5a, as in the corresponding provision of GPLv2, the notices

must state ``the date of any change,'' which we interpret to mean the date of

one or more of the licensee's changes.  The best practice would be to include

the date of the latest change.  However, in order to avoid requiring revision

of programs distributed under ``GPL version 2 or later,'' we have retained

the existing wording.

% FIXME:  It's now (b) and (c).  Also, ``validity'' of proprietary

%         relicensing?  Give me a break.  I'll fix that.

Subsection 5b is the central copyleft provision of the license.  It now

states that the GPL applies to the whole of the work.  The license must be

unmodified, except as permitted by section 7, which allows GPL'd code to be

combined with parts covered by certain other kinds of free software licensing

terms. Another change in subsection 5b is the removal of the words ``at no

charge,'' which was often misinterpreted by commentators.  The last sentence

of subsection 5b explicitly recognizes the validity of disjunctive

dual-licensing.

%  FIXME: 5d.  Related to Appropriatey Legal notices

% follows 5d now, call it the ``final paragraph''

The paragraph following subsection 5c has been revised for clarity, but the

underlying meaning is unchanged. When independent non-derivative sections are

distributed for use in a combination that is a covered work, the whole of the

combination must be licensed under the GPL, regardless of the form in which

such combination occurs, including combination by dynamic linking. The final

sentence of the paragraph adapts this requirement to the new compatibility

provisions of section 7.

\section{GPLv3~\S6: Non-Source and Corresponding Source}

Section 6 of GPLv3, which clarifies and revises GPLv2 section 3, requires

distributors of GPL'd object code to provide access to the corresponding

source code, in one of four specified ways. As noted above, ``object code''

in GPLv3 is defined broadly to mean any non-source version of a work.

% FIXME:  probably mostly still right, needs some updates, though.

Subsections 6a and 6b now apply specifically to distribution of object code

in a physical product. Physical products include embedded systems, as well as

physical software distribution media such as CDs. As in GPLv2, the

distribution of object code may either be accompanied by the machine-readable

source code, or it may be accompanied by a written offer to provide the

machine-readable source code to any third party. GPLv3 clarifies that the

medium for software interchange on which the machine-readable source code is

provided must be a durable physical medium. Subsection 6b does not prevent a

distributor from offering to provide source code to a third party by some

other means, such as transmission over a network, so long as the option of

obtaining source code on a physical medium is presented.

% FIXME:  probably mostly still right, needs some updates, though.

Subsection 6b revises the requirements for the written offer to provide

source code. As before, the offer must remain valid for at least three

years. In addition, even after three years, a distributor of a product

containing GPL'd object code must offer to provide source code for as long as

the distributor also continues to offer spare parts or customer support for

the product model. We believe that this is a reasonable and appropriate

requirement; a distributor should be prepared to provide source code if he or

she is prepared to provide support for other aspects of a physical product.

% FIXME: 10x language is gone.

Subsection 6b also increases the maximum permitted price for providing a copy

of the source code. GPLv2 stated that the price could be no more than the

cost of physically performing source distribution; GPLv3 allows the price to

be up to ten times the distributor's cost. It may not be practical to expect

some organizations to provide such copies at cost. Moreover, permitting such

organizations to charge ten times the cost is not particularly harmful, since

some recipient of the code can be expected to make the code freely available

on a public network server. We also recognize that there is nothing wrong

with profiting from providing copies of source code, provided that the price

of a copy is not so unreasonably high as to make it effectively unavailable.

% FIXME:  probably mostly still right, needs some updates, though.

Subsection 6c gives narrower permission than the corresponding subsection in

GPLv2.  The option of including a copy of an offer received in accordance

with subsection 6b is available only for private distribution of object code;

moreover, such private distribution is restricted to ``occasional

non-commercial distribution.''  This subsection makes clear that a

distributor cannot comply with the GPL merely by making object code available

on a publicly-accessible network server accompanied by a copy of the written

offer to provide source code received from an upstream distributor.

% FIXME:  probably mostly still right, needs some updates, though.

New subsection 6d, which revises the final paragraph of GPLv2 section 3,

addresses distribution of object code by offering access to copy the code

from a designated place, such as by enabling electronic access to a network

server.  Subsection 6d clarifies that the distributor must offer equivalent

access to copy the source code ``in the same way through the same place.''

This wording permits a distributor to offer a third party access to both

object code and source code on a single network portal or web page, even

though the access may include links to different physical servers.  For

example, a downstream distributor may provide a link to an upstream

distributor's server and arrange with the operator of that server to keep the

source code available for copying for as long as the downstream distributor

enables access to the object code.  This codifies what has been our

interpretation of GPLv2.

%FIXME: 6e, peer-to-peer

%  FIXME: Not final paragraph anymore. 

The final paragraph of section 6 takes account of the fact that the Complete

Corresponding Source Code may include added parts that carry non-GPL terms,

as permitted by section 7.

% FIXME: update lock-down section to work with more recent drafts

Though the definition of Complete Corresponding Source Code in the second

paragraph of section 1 is expansive, it is not sufficient to protect users'

freedoms in many circumstances. For example, a GPL'd program, or a modified

version of such a program, might need to be signed with a key or authorized

with a code in order for it to run on a particular machine and function

properly. Similarly, a program that produces digitally-restricted files might

require a decryption code in order to read the output.

The third paragraph of section 1 addresses this problem by making clear that

Complete Corresponding Source Code includes any such encryption,

authorization, and decryption codes. By requiring the inclusion of this

information whenever the GPL requires distribution of Complete Corresponding

Source Code, we thwart efforts to obstruct the goals of the GPL, and we

ensure that users will remain in control over their own machines. We

recognize an exception where use of the program normally implies that the

user already has the codes. For example, in secure systems a computer owner

might possess any keys needed to run a program, while the distributor of the

program might not have the keys.

% FIXME: installation information

%FIXME: publicly documented format

\section{Understanding License Compatibility}

\label{license-compatibility}

% FIXME: reword intro to license compatibility

Another challenge facing the free software community is the proliferation of

incompatible free software licenses. Of course, we cannot make the GPL

compatible with all such licenses. GPLv3 contains provisions that are

designed to reduce license incompatibility by making it easier for developers

to combine code carrying non-GPL terms with GPL'd code.

\section{GPLv3~\S7: Explicit Compatibility}

% FIXME:  probably mostly still right, needs some updates, though.

In GPLv3 we take a new approach to the issue of combining GPL'd code with

code governed by the terms of other free software licenses. Our view, though

it was not explicitly stated in GPLv2 itself, was that GPLv2 allowed such

combinations only if the non-GPL licensing terms permitted distribution under

the GPL and imposed no restrictions on the code that were not also imposed by

the GPL. In practice, we supplemented this policy with a structure of

exceptions for certain kinds of combinations.

% FIXME:  probably mostly still right, needs some updates, though.

Section 7 of GPLv3 implements a more explicit policy on license

compatibility. It formalizes the circumstances under which a licensee may

release a covered work that includes an added part carrying non-GPL terms. We

distinguish between terms that provide additional permissions, and terms that

place additional requirements on the code, relative to the permissions and

requirements established by applying the GPL to the code.

% FIXME:  probably mostly still right, needs some updates, though.

Section 7 first explicitly allows added parts covered by terms with

additional permissions to be combined with GPL'd code. This codifies our

existing practice of regarding such licensing terms as compatible with the

GPL. A downstream user of a combined GPL'd work who modifies such an added

part may remove the additional permissions, in which case the broader

permissions no longer apply to the modified version, and only the terms of

the GPL apply to it.

% FIXME:  probably mostly still right, needs some updates, though.

In its treatment of terms that impose additional requirements, section 7

extends the range of licensing terms with which the GPL is compatible. An

added part carrying additional requirements may be combined with GPL'd code,

but only if those requirements belong to an set enumerated in section 7. We

must, of course, place some limit on the kinds of additional requirements

that we will accept, to ensure that enhanced license compatibility does not

defeat the broader freedoms advanced by the GPL. Unlike terms that grant

additional permissions, terms that impose additional requirements cannot be

removed by a downstream user of the combined GPL'd work, because no such user

would have the right to do so.

% FIXME:  probably mostly still right, needs some updates, though.

Under subsections 7a and 7b, the requirements may include preservation of

copyright notices, information about the origins of the code or alterations

of the code, and different warranty disclaimers. Under subsection 7c, the

requirements may include limitations on the use of names of contributors and

on the use of trademarks for publicity purposes. In general, we permit these

requirements in added terms because many free software licenses include them

and we consider them to be unobjectionable. Because we support trademark fair

use, the limitations on the use of trademarks may seek to enforce only what

is required by trademark law, and may not prohibit what would constitute fair

use.

% FIXME: 7d-f

% FIXME:  removing additional restrictions

% FIXME:  probably mostly still right, needs some updates, though.

Section 7 requires a downstream user of a covered work to preserve the

non-GPL terms covering the added parts just as they must preserve the GPL, as

long as any substantial portion of those parts is present in the user's

version.

\section{GPLv3~\S8: A Lighter Termination}

% FIXME:  probably mostly still right, needs some updates, though.

GPLv2 provided for automatic termination of the rights of a person who

copied, modified, sublicensed, or distributed a work in violation of the

license.  Automatic termination can be too harsh for those who have committed

an inadvertent violation, particularly in cases involving distribution of

large collections of software having numerous copyright holders.  A violator

who resumes compliance with GPLv2 would need to obtain forgiveness from all

copyright holders, but even to contact them all might be impossible.

% FIXME: needs to be updated to describe more complex termination

Section 8 of GPLv3 replaces automatic termination with a non-automatic

termination process.  Any copyright holder for the licensed work may opt to

terminate the rights of a violator of the license, provided that the

copyright holder has first given notice of the violation within 60 days of

its most recent occurrence. A violator who has been given notice may make

efforts to enter into compliance and may request that the copyright holder

agree not exercise the right of termination; the copyright holder may choose

to grant or refuse this request.

% FIXME: needs to be updated to describe more complex termination

If a licensee who is in violation of GPLv3 acts to correct the violation and

enter into compliance, and the licensee receives no notice of the past

violation within 60 days, then the licensee need not worry about termination

of rights under the license.

\section{GPLv3~\S9: Acceptance}

% FIXME

\section{GPLv3~\S10: Explicit Downstream License}

% FIXME

\section{GPLv3~\S11: Explicit Patent Licensing}

\label{GPLv3s11}

% FIXME:  probably needs a lot of work, these provisions changed over time.

GPLv3 adds a new section on licensing of patents. GPLv2 relies on an implied

patent license. The doctrine of implied license is one that is recognized