Sleepycat's acquisition this week is a poigniant reminder of how licenses that call themselves "open" or "free" often come with strings attached, and why Foundations like Eclipse and Apache are so important.
Quick quiz: what do Sleepycat, JBoss, and MySQL have in common? A dual license - one free (but viral) and one commercial. To be really effective, the free side of the license has to be truly anathema to commercial interests, like GPL. Nobody can make money off of licensing software with a free license. Services, bundling, etc., sure, but not the software itself. I don't care whether you're talking beer or speech. For free software purists, it should end there.
But wait, there's money to be made, so greed raises its familiar head. Most of Sleepycat's revenue was from selling the paid commercial licenses. I don't see how people can say, on the one hand, that software wants its freedom, but on the other hand, only if it's not used commercially. Unless you're the author of course. "If anybody's going to make money off my software then it darned well better be me;" is that the argument? And Marc wants how much for JBoss?
But what about those big bad companies that take your code and stick it in their proprietary products never to see the light of day again? Don't you need a viral license to prevent that? No, what you need is a"reciprocal" license like EPL which requires modifications and bug fixes in the code you wrote to be given back under the same license. It's true that somebody (maybe other than you) can profit from the code, but at least you can profit from their improvements.
If you really want to ensure true freedom of your code, put it under the control of a Foundation like Apache or Eclipse. Foundations are not controlled by any one company so you can feel comfortable about being on a level playing field with your competitors. And Foundations aren't going to be bought by anybody. The stragglers are questionable bets. For example I was once looking at using Mondrian, but it was bought by Pentaho, a competitor. I was looking at Sleepycat but now it's owned by another competitor.
No matter how many times your competitor says you can trust their intentions, whose best interest do you think they have in mind?