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0 pointsrhinoceraptor7y ago0 comments

I think they're mistaking Qt Creator with Qt itself. Certainly if you're using Qt in your application, you need a license or release as L?GPL. The IDE/editor has nothing to do with it.

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4 comments · 2 top-level

detaro7y ago· 2 in thread

LGPL (and not GPL) specifically means that you do not need to release your application under an open license.

Small parts of Qt for specialized applications are under GPL, and abiding LGPL in embedded hardware is hard, but for normal desktop software it's not a problem.

rhinoceraptorOP7y ago

If you statically link to QT, that’s a derivative work so you need to release as GPL or buy a proprietary license.

detaro7y ago

That's why approximately nobody links Qt statically on desktop systems. (technically you can also share compiled, proprietarily licensed object files a customer can re-link themselves, but I suspect that's even rarer) I should maybe have clarified that above what obligations the LGPL does bring, but that case basically matters only on mobile and embedded.

KingMachiavelli7y ago

Based off of Qt's comparison between their commercial and open source licenses, you would only absolutely need the commercial license if you were making modifications to Qt itself instead of linking to the shared libraries. Even in that case you could simply publish your Qt modifications as GPL seperetly.

https://www.qt.io/download

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