"It's official: Microsoft will not accept any external code contributions to its planned Dynamic Language Runtime, which will run Microsoft's new scripting languages for the web and Silverlight content on .NET. Microsoft will, though, continue to accept source-code contributions to its slowly emerging implementation of Ruby for .NET, IronRuby. Contributions are helping to build IronRuby and shepherd the language towards the first-full release. The Register has learned, meanwhile, that Microsoft will start accepting external contributions to its other great scripting language project, putting Python on .NET - IronPython - in the "near future". The promise by Microsoft IronRuby lead John Lam comes nearly a year after the topic was first raised. The reason Microsoft decided to leave the DLR closed, despite taking contributions to the languages that will run inside it, is to protect itself from unwanted licenses and IP claims."