After a bit of digging, I learned that BitKeeper has, as a part of its EULA, a provision that disallows its users to contribute to other source control projects

After a bit of digging, I learned that BitKeeper has, as a part of its EULA, a provision that disallows its users to contribute to other source control projects[1]. Larry McVoy (aka luckydude) has actually tried to enforce the EULA by contacting the users' employers to get them to stop contributing, but my guess is that he never took it to court because, well, he would be laughed right back out again. As for Mercuiral, one of the early developers, Bryan O'Sullivan, apparently worked for a company that used BK, and McVoy told him that he had to stop contributing[2] to the project, which he did[3]. O'Sullivan is now showing up in the commit history again, which I presume means he's no longer working for a company that uses BK. [1] http://yro.slashdot.org/story/02/10/06/0518220/BitKeeper-EULA-Forbids-Working-On-Competition http://yro.slashdot.org/story/02/10/06/0518220/BitKeeper-EUL... [2] http://en.wikipedia.org/wiki/Bitkeeper#Pricing_change http://en.wikipedia.org/wiki/Bitkeeper#Pricing_change [3] http://article.gmane.org/gmane.comp.version-control.mercurial.devel/3481 http://article.gmane.org/gmane.comp.version-control.mercuria...