The first question to ask is 'what is the intent of providing the SDK?'. I assume that the intent of the SDK is to encourage developers to create add-ons for the service with the hope that the existence of third party add-ons will attract new customers. Within this there are more decisions about the intellectual property, licensing, and contributions:

Option 1: We are not concerned about IP issues of the SDK (as it is mainly an API auto-generated from the service WSDLs). We are not concerned about making money from the developers. We like the idea of developers helping us test and maintain the API.

• In this case a very permissive license such as BSD or Apache will be a good choice.

Option 2: We are not concerned about IP issues of the SDK (as it is mainly an API auto-generated from the service WSDLs). We are concerned about developers making money from the API - if they make money we feel we should receive some of that revenue.

• In this case a dual license (GPL/commercial) makes sense. Developers using the GPL license will have to provide their source code to anyone using their software - developers that don't like this license will pay you for a commercial (non-GPL) license to use the same API.

Option 3: We are not concerned about receiving coding or quality contributions from developers. We want to maintain control of access to the API - we want to know who is developing and what they are developing. We may or may not charge for developing using the API.

• In this case a proprietary API makes sense. You can charge for it or make it freeware.

This would be a good topic to discuss in the context of the Franklin Street Statement, and the autonomo.us community in general. I think that the interest of a free network for its users does require that service SDKs be free.