possibly controversial question: "Can I create commercial software using SageMath?"

[William Stein]

http://ask.sagemath.org/question/34442/can-i-create-commercial-software-using-sagemath

I put: "ANSWER: It depends on what you mean by "commercial software".

ONE: If by "commercial software" you mean "closed source", then the
answer is no, you can't write and publicly distribute such software
legally.

If you write a program that genuinely uses the Sage library in a
nontrivial way, then that program is a derived work of Sage and must
be distributed under the GPL (after all, there is no possible way to
run the program without calling many functions in Sage).

When I started Sage, I took PARI -- a GPL'd program -- and started
building Sage on top of that. I was forced to GPL Sage because it was
a derived work of PARI. It's the same principle at work. Sage is very
much a LIBRARY, not just a programming language.

We (Sage developers) also cannot sell or provide you with an
exception, because Sage itself depends on many GPL'd programs that we
do not own the copyright to.

TWO: If by "commercial software" you mean software that makes money",
then yes, it is possible to build commercial software on top of GPL'd
software such as Sage. E.g., SageMathCloud is commercial (it makes
money) but is GPL'd. The Linux operating system is also GPL'd but
there are companies (like RedHat and Ubuntu) that make money from that
software."


--
William (http://wstein.org)

[Bill Hart]

Disappointed. That's about as controversial as the pope being a catholic.

Bill.

[rjf]

Disclaimer: I am not a lawyer.

Not the way I understand it, but I suppose it matters what you mean by create.

If you use Sage(Math) to derive a formula that you then incorporate into your

commercial closed-source program,  I think the answer is, that's OK.

If you use your commercial closed-source program to access SageMath, or Sage

that's OK also.  Otherwise you would not be allowed to acess Sage from Windows.

If you take the source code for Sage and hide it inside your commercial closed-source

program, you are probably violating the GPL terms.

And as William says, you can always try to sell something that is GPL free.

Of course, I once again remind you,  I am not a lawyer.

RJF

[Robert Dodier]

On 2016-08-17, William Stein <wst...@gmail.com> wrote:

> If you write a program that genuinely uses the Sage library in a
> nontrivial way, then that program is a derived work of Sage

Well, if there is any controversy here, it must be this statement. The
question of what constitutes a derived work is subtle and complex, and I
don't think any categorical statements are possible. An exploration of
this topic that I've found useful is this "Twenty Questions about the
GPL": https://jacobian.org/writing/gpl-questions/

I know that various parties have offered their opinions about what
constitutes a derived work, including the FSF, the institution behind
the GPL. But even the FSF's interpretation isn't binding on anybody --
whether some work falls under the GPL depends on copyright law, which
can only be decided by a court, not the you, me, or the FSF, and even
then we don't have a whole lot of court cases to guide us.

Lay discussions about the GPL tend to contain a lot of wishful thinking
alternating with the frank admission that nobody really knows and
therefore if there's any question, one must hire a lawyer. Surely,
though, a large group of intelligent, motivated people can formulate
some clear guidelines. For a start, perhaps sorting out the twenty cases
mentioned above into probably yes, probably no, and everything else.
Just guessing here; doubtless there are better ideas.

Incidentally, if ever a lawyer has weighed in on licensing issues
related to Sage, I would be interested to hear about it. Also, I haven't
been paying attention, so if there have been previous discussions about
the GPL and Sage, I apologize for trotting out a tired argument.

FWIW

Robert Dodier

[William Stein]

Thanks -- that's an extremely good point. I should amend my statement
to: "If you write a program that genuinely uses the Sage library in a
nontrivial way, then it **may** be a derived work of Sage. In that
case... [GPL ...]"


--
William (http://wstein.org)

[Volker Braun]

On Saturday, August 20, 2016 at 2:28:58 AM UTC+2, Robert Dodier wrote:

I know that various parties have offered their opinions about what
constitutes a derived work, including the FSF, the institution behind
the GPL. But even the FSF's interpretation isn't binding on anybody --
whether some work falls under the GPL depends on copyright law, which
can only be decided by a court, not the you, me, or the FSF, and even
then we don't have a whole lot of court cases to guide us.

That has nothing to do with software, if you want a legally binding interpretation of anything then you have to go to court.

And, as you know, if there is any question about interpretation then the court will almost certainly side with the interpretations written previously by the FSF, so in practice the FSF's interpretation does matter. Since there can be quite some money involved its quite certain that somebody would have produced a court case had they seen a reasonable chance of success in challenging the FSF's interpretation.

[cir...@gmail.com]

I will add this: I'm a retired developer with 35+ years of writing commercial software, and I will gladly give my time, effort, and expertise to open source software so that enthusiasts, students, amateurs, teachers, and many others can benefit from it. However if it ever gets to the point where some person or company is making a significant amount of money from my freely given efforts, I doubt very much I would continue.

One of the reasons I chose Sage as a project I would contribute to is that, besides my lifelong love of mathematics, I felt that most of the users of this software would be individuals who weren't using it to make money. Maybe I'm naive about that, but I don't think so. There's a lot of open source projects out there that I wouldn't be part of simply because there are so many companies using that software for their own profit. I suspect there are a lot of open source contributors that feel the same way.

-Bill

[William Stein]

On Sat, Aug 20, 2016 at 8:15 AM, <cir...@gmail.com> wrote:
> I will add this: I'm a retired developer with 35+ years of writing
> commercial software, and I will gladly give my time, effort, and expertise
> to open source software so that enthusiasts, students, amateurs, teachers,
> and many others can benefit from it. However if it ever gets to the point
> where some person or company is making a significant amount of money from my
> freely given efforts, I doubt very much I would continue.
>
> One of the reasons I chose Sage as a project I would contribute to is that,
> besides my lifelong love of mathematics, I felt that most of the users of
> this software would be individuals who weren't using it to make money. Maybe
> I'm naive about that, but I don't think so. There's a lot of open source
> projects out there that I wouldn't be part of simply because there are so
> many companies using that software for their own profit. I suspect there are
> a lot of open source contributors that feel the same way.
>
> -Bill

So there is no confusion, my top priority right now is to **make a lot
of money** by building a profitable company on open source software
(Latex, Linux, Sage, Octave, R, etc.), and use that money to fund:

1. Sage development,

2. Vastly improve the *documentation* ecosystem around Sage,

3. Vastly improve the *support* ecosystem around Sage, especially
for the masses beyond elite research mathematicians.

You may strongly disagree with this, or chose not to be involved in
Sage (or LInux, say) as a result. But to be clear -- I'm not hiding
this.

-- William

> --
> You received this message because you are subscribed to the Google Groups
> "sage-devel" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to sage-devel+...@googlegroups.com.
> To post to this group, send email to sage-...@googlegroups.com.
> Visit this group at https://groups.google.com/group/sage-devel.
> For more options, visit https://groups.google.com/d/optout.



--
William (http://wstein.org)

[cir...@gmail.com]

What is the name of the company you're referring to?

[William Stein]

On Saturday, August 20, 2016, <cir...@gmail.com> wrote:

What is the name of the company you're referring to?

https://Cloud.sagemath.com

To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscribe@googlegroups.com.

To post to this group, send email to sage-...@googlegroups.com.
Visit this group at https://groups.google.com/group/sage-devel.
For more options, visit https://groups.google.com/d/optout.

--
Sent from my massive iPhone 6 plus.

[Robert Dodier]

On 2016-08-20, Volker Braun <vbrau...@gmail.com> wrote:

> And, as you know, if there is any question about interpretation then
> the court will almost certainly side with the interpretations written
> previously by the FSF, so in practice the FSF's interpretation does
> matter.

I hadn't heard about that. Can you refer to some cases in which the
court relied on the FSF interpretation?

best,

Robert Dodier

[Dima Pasechnik]

business cases are mostly settled out of court. There was a number of litigations (co)ged by FSF:

https://wiki.fsfe.org/Migrated/GPL%20Enforcement%20Cases

but none of these went as far as to actual court sittings.

 

best,

Robert Dodier