See this explainer by the FSF: https://www.gnu.org/philosophy/categories.html
- have a notice that you modified it,
- have a notice that the work is licensed under the GPL,
- be licensed under the GPL, and
- if the work has interactive UIs, it must display Appropriate Legal Notices.
It says nothing about contributing changes back, the only freedom it restricts is the "freedom" to restrict the freedom of others. It is like the whole "is prohibiting slavery reducing freedom" problem.
Except there are dozens of incompatible (A/L)GPL (2,3) licenses alone and an uncountable number of minor modifications of the same. So you end up with the "freedom" not to share code between various GPLed projects because they all are slightly different flavors of free.
You have to keep reading the entire license...
Section 6 of v3 begins:
You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:
a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
<or several other functionally similar ways are options in the full text linked below>
How is that not needing to convey your source changes to those whom you distribute the object code?
It’s been there since v1:
Paragraph 3 of the v1 or v2 GPL is similar to section 6 of v3:
You may copy and distribute the Program (or a portion or derivative of it, under Paragraph 2) in object code or executable form under the terms of Paragraphs 1 and 2 above provided that you also do one of the following:
a) accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Paragraphs 1 and 2 above; or,
<do other things that have the same effect>
I personally wouldn't consider the second interpretation as "paying" for Free Software any more as I would consider having people publically criticise me as "paying" for Free Expression.
If that’s upstream, then you have to offer them upstream. If that’s to someone else who then decides to share them upstream, that’s also something you can’t prevent.
If you don’t distribute the program, you don’t have to send your changes anywhere.
(My main point was your citation of only Section 5 was incomplete with regards to your obligations under GPL.)
Also the free but not really has already a name, called shareware. I think it's just their marketing ability that they managed to be called free software, despite the definition of the word. (But GPL is not really about the price of the software, they aim to be free as freedom, but .. they are not.)
I think that sums up the root of the entire debate. :)
> obligated
....so, basically, Free as in Slavery?
Seriously, I'm not going to stand by and watch GNU partisans try to rewrite history.
Stallman did a lot of things, but he most definitely did not start the free software movement. Free software was the norm prior to the meeting of the Committee on New Technology Uses (CONTU) suggesting in 1977 that rather than try to amend the recently passed Copyright Act of 1976 they should just classify software as 'literature'. It continued to be the norm and was openly termed "Freeware" by author Jay Lucas at InfoWorld (until a certain lawyer, Andrew Fluegelman, trademarked the term and began threatening legal action if he didn't change the name of his "Freeware" column, leading to a contest which suggested the term "Shareware"). Most freeware of the time came with source code and the right to make modifications (in fact this is how a number of improvements were made to Fluegelman's own PC-TALK). It wasn't until after the coining of Shareware that the two terms were hijacked by people essentially using it to create freely recirculatable demos of otherwise proprietary products, much like 'free software' was later repackaged as 'open source'.
I'm not saying you shouldn't be thankful for his contributions, but to pretend that BSD didn't exist, nor an entire tradition of free software prior to the rise of proprietary software, is simply wrong.