Duncan Booth <[EMAIL PROTECTED]> writes: > Mr.SpOOn wrote: > > What's the problem with qt licence? > > "You must purchase a Qt Commercial License from Qt Software or from > one of its authorized resellers before you start developing > commercial software. The Commercial license does not allow the > incorporation of code developed with the Open Source Edition of Qt > into a commercial product."
This text is at <URL:http://trolltech.com/products/appdev/licensing>, for those following along at home. The above statement is confusing and misleading. There is nothing about the GPL that prevents commercial software; in fact, selling software to support development is positively encouraged. The GPL itself explicitly says this. GPL version 2: “You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.” GPL version 3: “You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.” What that page says could be correct if, instead of falsely claiming that *commercial* software requires a separate license, it rather said that if you want to redistribute Qt with *restrictions* on the recipient additional to those in the GPL, you cannot use the GPL as the license. They offer a separate license (the confusingly-named “commercial license”) that permits some additional restrictions on the recipient of your software. > In effect this means that if you want to develop any commercial > software with Qt you have to buy the license in advance (even if all > you want is to knock together some proof-of-concept) and you are > also permanently locked out from including any previously developed > Qt code which the wider community may have produced. That is a common misconception, which is not made any better by misleading text like that found at the above page, and misleading dichotomies like GPL versus “commercial license”. A careful reader of the GPL will see that there is explicitly *no* restriction placed on redistributing the work commercially: any fee may be charged. > With other GPL licensed software you have the option of approaching > the original author and negotiating with them for their code to be > relicensed for use within your proprietary product This option remains with Qt also, of course, Anyone is free to attempt such negotiations. > It is a novel interpretation of the GPL. Qt Software have every > right to impose this sort of condition, but it makes me want to > avoid them. No, they have no such right to interpret the GPL this way; it would be entirely incompatible with the GPL since it would be an imposition of additional restrictions, resulting in work that could not legally be redistributed at all. In fact, I don't think they are making such an interpretation, though their poorly-worded web page that you quoted certainly encourages readers to make such a false interpretation. -- \ “I know you believe you understood what you think I said, but I | `\ am not sure you realize that what you heard is not what I | _o__) meant.” —Robert J. McCloskey | Ben Finney -- http://mail.python.org/mailman/listinfo/python-list
