4 ms·

Dear lazyweb, what exactly is Qt's current business? The blog post makes it sound as if the commercial version of Qt wasn't free software. What freedoms does it

by jordigh 12y ago

Dear lazyweb, what exactly is Qt's current business? The blog post makes it sound as if the commercial version of Qt wasn't free software. What freedoms does it take away? I know that Trolltech commercialised Qt by selling exceptions. What's the current business? Also, if 25% of all contributions are coming from non-Digia employees, does Digia require copyright assignment? Does their current commercial model require copyright assignments?

avar 12y ago
Yes, they release it under GPL/LGPL and make their money on proprietary licenses for users that can't or won't use those licenses. If you want to develop Qt itself and get your changes included you have to sign a copyright assignment agreement that gives Digia the right to re-license your work. See: http://qt-project.org/doc/qt-5/licensing.html http://qt-project.org/legal.html
milliams 12y ago
They sell a commercial version without any restrictions on usage. In order to accommodate this they do have a copyright license to Digia (https://codereview.qt-project.org/static/cla_individual.html https://codereview.qt-project.org/static/cla_individual.html).
- jordigh 12y ago
  > They sell a commercial version without any restrictions on usage. I understand I can't give it to my friends? That's would be a restriction that free software/open source doesn't have.
  - milliams 12y ago
    You can give it to your friends since all you have is a license to use the source-code under different conditions. It's the same source either way, just you have a special license. Your friends don't have that license and so presumably would be bound by the LGPL.
    - jordigh 12y ago
      Apparently not all of it, there are some non-free addons not available under a free license.
cbhl 12y ago
Qt is licensed under GPL v3 and LGPL v2.1, but you can also buy a license if you want to use and/or modify Qt in a project without having to redistribute the whole thing under GPLv3 or redistribute your modified Qt under LGPL v2.1. There's actually a lot of closed-source software you know of that uses Qt in some form: Autodesk Maya, Google Earth, Skype, and Spotify are just a few. I'm not sure whether all of these teams use the commercial version (some may use e.g. the LGPL version) but it's probably not zero. http://en.wikipedia.org/wiki/Qt_(software)#Software_using_Qt http://en.wikipedia.org/wiki/Qt_(software)#Software_using_Qt
- jordigh 12y ago
  So they're back to selling exceptions again? I thought they had stopped when it was owned by Nokia.
  - navlelo 12y ago
    The commercial business/licensing was sold off to Digia, which eventually bought the whole Qt division.
    - jordigh 12y ago
      Yes, I understand this, but Digia went back to GPL and back to selling GPL exceptions like Trolltech did originally?
      - milliams 12y ago
        No. it's still available under the LGPL.
      - toyg 12y ago
        Digia is doing the same thing Nokia did, which was the same thing Trolltech did. The only difference is that, since the Nokia takeover, the open source version is also available under LGPL. This has not changed under Digia.
      - 12y ago
zanny 12y ago
They also have a bunch of addon packs that are proprietary-only. A few of them would be really useful in the free software community too, which sucks, like their graphing QML library.
- jordigh 12y ago
  So the commercial version indeed is not open source at all? I can't buy the commercial version and give it to my friends? Hm. That's a pity.
  - milliams 12y ago
    Two separate things: 1) The Qt source code. Available under GPL, LGPL or commercial license 2) Some extra proprietary addons. Only available under the commercial license.
    - jordigh 12y ago
      I don't get it, why would anyone buy an LGPL exception? They want to keep their own private Qt fork and keep the modifications to Qt locked up? Is the cost of maintaining a private fork really that profitable and much lower than the cost of buying an LGPL exception? I'm just surprised that's a good business model too. I don't quite understand it. Maybe there's something I could read instead of asking the lazyweb?
      - zanny 12y ago
        You don't need to read much, the answer is simple: legal departments. For most companies, the lawyers don't understand the LGPL or software at all, so they don't understand that the LGPL lets the company distribute binaries with Qt libraries included without any source release requirements. They just need to include a notice that Qt is used and where to get the LGPL parts source. They just like being able to pay money and "own" the IP. The only time a company actually needs the commercial option is when they distribute in house modified Qt libraries, because those would be derivative works. And I would really want to know why the hell any company thinks its worth it to buy a commercial license so they don't have to release their modifications to Qt itself. That is just ridiculous.

by jordigh 12y ago

avar 12y ago

Yes, they release it under GPL/LGPL and make their money on proprietary licenses for users that can't or won't use those licenses. If you want to develop Qt itself and get your changes included you have to sign a copyright assignment agreement that gives Digia the right to re-license your work. See: http://qt-project.org/doc/qt-5/licensing.html http://qt-project.org/legal.html

milliams 12y ago

They sell a commercial version without any restrictions on usage. In order to accommodate this they do have a copyright license to Digia (https://codereview.qt-project.org/static/cla_individual.html https://codereview.qt-project.org/static/cla_individual.html).

jordigh 12y ago
> They sell a commercial version without any restrictions on usage. I understand I can't give it to my friends? That's would be a restriction that free software/open source doesn't have.
- milliams 12y ago
  You can give it to your friends since all you have is a license to use the source-code under different conditions. It's the same source either way, just you have a special license. Your friends don't have that license and so presumably would be bound by the LGPL.
  - jordigh 12y ago
    Apparently not all of it, there are some non-free addons not available under a free license.

cbhl 12y ago

Qt is licensed under GPL v3 and LGPL v2.1, but you can also buy a license if you want to use and/or modify Qt in a project without having to redistribute the whole thing under GPLv3 or redistribute your modified Qt under LGPL v2.1. There's actually a lot of closed-source software you know of that uses Qt in some form: Autodesk Maya, Google Earth, Skype, and Spotify are just a few. I'm not sure whether all of these teams use the commercial version (some may use e.g. the LGPL version) but it's probably not zero. http://en.wikipedia.org/wiki/Qt_(software)#Software_using_Qt http://en.wikipedia.org/wiki/Qt_(software)#Software_using_Qt

jordigh 12y ago
So they're back to selling exceptions again? I thought they had stopped when it was owned by Nokia.
- navlelo 12y ago
  The commercial business/licensing was sold off to Digia, which eventually bought the whole Qt division.
  - jordigh 12y ago
    Yes, I understand this, but Digia went back to GPL and back to selling GPL exceptions like Trolltech did originally?
    - milliams 12y ago
      No. it's still available under the LGPL.
    - toyg 12y ago
      Digia is doing the same thing Nokia did, which was the same thing Trolltech did. The only difference is that, since the Nokia takeover, the open source version is also available under LGPL. This has not changed under Digia.
    - 12y ago

zanny 12y ago

They also have a bunch of addon packs that are proprietary-only. A few of them would be really useful in the free software community too, which sucks, like their graphing QML library.

jordigh 12y ago
So the commercial version indeed is not open source at all? I can't buy the commercial version and give it to my friends? Hm. That's a pity.
- milliams 12y ago
  Two separate things: 1) The Qt source code. Available under GPL, LGPL or commercial license 2) Some extra proprietary addons. Only available under the commercial license.
  - jordigh 12y ago
    I don't get it, why would anyone buy an LGPL exception? They want to keep their own private Qt fork and keep the modifications to Qt locked up? Is the cost of maintaining a private fork really that profitable and much lower than the cost of buying an LGPL exception? I'm just surprised that's a good business model too. I don't quite understand it. Maybe there's something I could read instead of asking the lazyweb?
    - zanny 12y ago
      You don't need to read much, the answer is simple: legal departments. For most companies, the lawyers don't understand the LGPL or software at all, so they don't understand that the LGPL lets the company distribute binaries with Qt libraries included without any source release requirements. They just need to include a notice that Qt is used and where to get the LGPL parts source. They just like being able to pay money and "own" the IP. The only time a company actually needs the commercial option is when they distribute in house modified Qt libraries, because those would be derivative works. And I would really want to know why the hell any company thinks its worth it to buy a commercial license so they don't have to release their modifications to Qt itself. That is just ridiculous.