[Interest] Licensing

Tuukka Turunen tuukka.turunen at qt.io
Wed Oct 9 13:45:40 CEST 2019

Hi Uwe,

This is not about making closed source applications with LGPL licensed Qt, or whatever kind of business is done with such.

The point is that Qt as a dual licensed technology has some rules related to the commercial license option. One of these rules is that the whole team should go commercial. That rule has nothing to do with any open-source license, but only the commercial license of Qt. Similar rule is related to not being ok to develop the solution with free version and then ship under commercial one. We do allow migration from open-source to commercial - of course. The case by case acceptance rule is there to avoid misuse.

I know that dual licensing can be complicated. For that reason it is best to talk with our local sales team when moving from open-source to commercial and look into the issue together with them. We aim to give a clear and correct view of this in our web pages, but as the topic has many angles, it is typically easiest to look into this on case by case basis when migrating to commercial. 

What comes to using FUD as sales strategy, that is not what we aim for at all. On the contrary we are actively trying to explain the dual licensing in the FAQ, videos, web pages, webinars, mailing lists etc exactly to relieve the U and D - and having enough and correct information helps with the Fear part as well. 



´╗┐On 09/10/2019, 12.07, "Interest on behalf of Uwe Rathmann" <interest-bounces at qt-project.org on behalf of Uwe.Rathmann at tigertal.de> wrote:

    On 10/8/19 7:13 PM, Ilya Diallo wrote:
    > In the latter case, the rational is (I guess) to prevent a company, 
    > say, to work with 20 developers for 3 years on an OSS Qt license, 
    > then switch to commercial when it's time to ship the product and the 
    > team is reduced to a core maintenance crew. That late switch is 
    > unfair to companies that are playing by the rule, ...
    Please allow me to quote Wikipedia:
    "The license allows developers and companies to use and integrate a
    software component released under the LGPL into their own (even
    proprietary) software without being required by the terms of a strong
    copyleft license to release the source code of their own components."
    The motivation for not using the LGPL - at least on the desktop - is
    usually, that you want to avoid its obligations, when linking
    statically. That's all.
    There is no inner logic behind bundling the commercial license with
    support contracts and the number of developers using it - beside, that
    the Qt company makes this connection.
    I don't have much opinion on this topic - not my business - but I don't
    agree that "fair/unfair" is a valid category in this context.
    But I have a strong opinion about using FUD as sales strategy:
    - intimidation paragraphs
    - blacklisting projects that follow the rules of the LGPL properly
    - giving wrong information ( check the video ) about the LGPL
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