Buy Qt License?

[qtoptus]

Working on a software that uses Qt 5.x for GUI. Do I need to buy a commercial license before start selling my closed-source program?

Thanks.

[wysota]

"It depends". In general if you require a commercial licence, you should acquire it before you start working on the software and not before you start selling it.

[qtoptus]

Depends on what?

[wysota]

Depends on how you use Qt. Mainly if you are going to violate the LGPL licence or not.

[qtoptus]

I know law can be a$$ and to avoid troubles is there any specialized lawyers or IT specialists to consult or even Digia to make sure I'm not violating their license?

Thanks.

[anda_skoa]

Rule of thumb: if you are shipping the unmodified Qt DLLs with your application you are fine with the LGPL license.

Cheers,
_