Lawyers and programmers have at least one thing in common: their day-to-day work puts them in contact with issues that seem obscure and esoteric to the general public. That makes the terms of open source licenses doubly difficult to understand, but Lawrence Rosen does an admirable job explaining them in his book.
The final four chapters cover choosing an open source license for your projects; licensing models other than open source; open source litigation; and open standards. In the first of these chapters, Rosen talks about what issues are usually taken into consideration when choosing an open source license for a project. In particular, he deals with the free-rider problem and how to make money from open source projects. Themes that were discussed earlier in the book (i.e. collective vs. derivative works, license compatibility, etc.) also reappear here.
In the second chapter of this section Rosen talks about alternatives to open source licenses. He covers Microsoft's shared source; public source, which allows licensees to make copies, create derivative works, and distribute their works, but draws the line at commercial uses for the software; and several other models as well. Rosen even discusses the special issues of combining licensing models, as Jabber has done with its instant messaging software (the client versions are open source, but the server versions are not).
Obviously, anyone thinking of licensing an open source project should read the chapter on open source litigation. Rosen covers SCO's litigation near the end of the chapter (though keep in mind the publication date of the book) but before that he takes a look at the likeliest issues to come up. He ends this chapter with the comforting knowledge that "as long as licensees honor the conditions of the licenses for software they accept, there is little reason to fear it will be taken away through litigation."
In the final chapter Rosen discusses open standards, distinguishing them from open source. He covers what open standards are, and how they interact with open source software. He also explains how open standards are enforced, how forks are discouraged, and more.
Rosen writes in an engaging, approachable style that can make even the subtlest distinctions clear. With the popularity of open source software and open source projects continuing to grow, this book belongs on the shelf of any programmer who desires to contribute to, or start, an open source software project.