I mean is there some open sourced projects that were started as closed source and were commercially successful also? I am also interested in any story behind open sourcing them.

  • 2
    If by commercially successful you don't imply 'paid', there's Netscape Navigator -> Mozilla. – K.Steff Jun 30 '12 at 16:11
  • 1
    Several commercial projects have been open sourced when being laid in the grave. You might want to consider if you are interested if the open source project is successful too. – user1249 Jun 30 '12 at 16:14
  • Here's the opposite, a open source gone commercial: Ranet Olap – Jeremy Thompson Jul 1 '12 at 0:23

Blender was initially commercial.

Update: this answer is far better than mine; upvote it instead.

  • 3
    This is an excellent example of another model, the community got together and bought (for real $) the company from it's original owners. – Martin Beckett Jun 30 '12 at 16:32

Some "Formerly Commercial-Only" Projects

  • The IntelliJ IDE was originally closed-source
  • A lot of Id Software games, old (like Wolfenstein 3D) and not so old (like Doom 3)
  • A lot of projects released as open-source by Sun Microsystems started as closed-source experiments or products:
    • the JDK and JRE themselves,
    • NetBeans (interesting crossing history lines between the Forte For Java and NetBeans names)
    • The Star Office suite (later to be super-seded by Open Office, and now forked as Libre Office)
  • The source of (some versions and some parts of) the Microsoft Windows kernel is actually available for educational purposes and partners.
  • ... and find many more just by using a search on a service like Google News

"Non-Commercial" / Internal Projects

There were also some non-commercial internal projects (used by a company or a group of companies, but not released to the general public) which got open-sourced after their end of life or after a while. For instance, NASA has been known to release a few things.


  • Some projects finally publish their source, but do not necessarily make it available under a copyleft or Free Software license.
  • Some projects are commercial but do publish their source to selected groups of people: in general universities, or partner enterprises. Depending on the licensing terms, you could argue this as being open-source.

Qt was originally a commercial project by Trolltech, then when they were bought by Nokia it was released as a dual (commercial/LGPL) project.

The value to Nokia of having it as the default GUI toolkit of programmers all over the world was more valuable than the extra license fees from a few commercial customers ( or it would have been if Nokia could project manage their way out of a paperbag)

  • @James it's not a question of how great Qt is or isn't. The question is why would Nokia give away something they paid $135M for – Martin Beckett Jun 30 '12 at 16:08
  • @James further it's a bit naive to think WP is a nothing. It's gaining popularity, slowly but surely. People are tired of the Apple/Android ecosystems, they want to try something new, and people are switching. It WP was bad, they wouldn't switch. – David Cowden Jun 30 '12 at 16:16
  • I was commenting on Nokia's Project Management prowess, not QT. (ex-Nokian) – James Jun 30 '12 at 16:19
  • Qt was released as open source before Nokia bought it. The X11 version was "open source" (for some definition of such) pretty much from the start. – Mat Jun 30 '12 at 16:29
  • It was free (beer) on X11 (don't remember the license) and they had a covenant for KDE that it would be open sourced if Trolltech ever dissapeared – Martin Beckett Jun 30 '12 at 16:31

Here you are the TOP list - 63 Top Commercial Open Source Projects

Even a better post to look at the trend in Community-driven Open Source Projects Become More Marketing Savvy


Java, it's a GPL project for the biggest part ( some minor pieces of code can have a different license ) since 2007

  • I do not think Java on its own have made Sun a lot of money. Perhaps some hard figures would be nice. – user1249 Jun 30 '12 at 16:49
  • 2
    The OP doesn't say anything about free software, but about open source. As far as I know, it's been Open Source for a loooootttt longer than that, especially if you consider the Java APIs for which the source has been available with the JDK for ages (and other things were available on request). I do think it wasn't originally open-source though. – haylem Jun 30 '12 at 20:21

Gish, Penumbra, Lugaru and Aquaria were open-sourced following the success of the first Humble Bundle promotion.


IIRC, Sun's Glassfish server was originally the Sun Java System Application Server, which was originally the SunONE Application Server, which started out as the iPlanet Application Server, which had been created by merging the code bases of the Netscape Enterprise Server and the NetDynamics Application Server.

Likewise, the EclipseLink project started out as a Smalltalk product (TopLink) which was ported to Java and eventually donated to Sun to be used as part of the Glassfish project, before finally finding its way to the Eclipse project.

Not the answer you're looking for? Browse other questions tagged or ask your own question.