Hi all, I recently received a request to implement the "retweet" api calls in the python-twitter and java-twitter libraries, but before I proceed I was hoping for a bit of clarification around the licensing terms for the Twitter API.
My layman's understanding is that without explicit terms there are relatively few rights offered by default regarding a specification. In particular, I have a few questions about copyright, trademark, and patents rights being offered to implementors of the Twitter API. My longstanding sense is that Twitter has indicated the spirit of offering the API under generally permissive usage rights, so hopefully this thread can move the discussion forward a bit and perhaps turn that spirit into something more formal. *Copyright* **Question: Under what terms may third-party library and application developers use the text and images associated with the Twitter API specification? Example use case: Third-party library developers would like to copy and/or modify the text of the Twitter API specification in the library's documentation. This is preferred over inventing new text for the documentation, the meaning of which could deviate from the canonical version in the Twitter API specification. Potential concern: Without a copyright license, implementors may not be permitted to use or reuse the Twitter API specification text in third-party library documentation. Current state: While the Twitter API specification itself doesn't mention copyright, the Twitter Terms of Service (http://twitter.com/tos) state: "The Services are protected by copyright, trademark, and other laws of both the United States and foreign countries," which could reasonably be interpreted to apply to the Twitter API service as well. Possible desired outcome: The Twitter API specification is made available under a permissive and derivative works-friendly copyright license, such as the Creative Commons BY or BY-SA license. *Trademark* Question: Under what terms may third-party library and application developers use the various registered service marks of Twitter, Inc? Example use case: Third-party library authors would like to use the words "twitter", "tweet", "retweet" (all live service marks of Twitter, Inc) in their libraries. This is preferred over third-party library authors inventing new terms for API methods such as "retweet". Potential concern: Without terms that specify where and how the various registered marks can be used, third-party library implementors may or may not be permitted to use terms such as "twitter", "tweet", "retweet", etc., in their libraries. Current state: The Twitter Terms of Service (http://twitter.com/tos) appear to prohibit such use: "Nothing in the Terms gives you a right to use the Twitter name or any of the Twitter trademarks, logos, domain names, and other distinctive brand features." Possible desired outcome: Twitter publishes acceptable-use guidelines for registered marks in third-party libraries and third-party applications. *Patent* Question: Under what terms may third-party library and application developers make use of current or future patent claims made by Twitter, Inc? Example use cases: A third-party developer may wish to implement an independent service that conforms to the Twitter API method signatures, or a third-party developer may wish to implement a library that implements portions of the Twitter API on the client. Potential concern: Without terms that specify how third-party developers may use patent claims (if any) made by Twitter, Inc, implementors assume the risk of potentially infringing on current or future claims made by Twitter. Current state: Twitter (to my knowledge) has made no statement regarding patent claims with respect to implementations of the Twitter API. Possible desired outcome: The Twitter API specification is made available under a patent agreement, such as the Open Web Foundation Agreement ( http://openwebfoundation.org/legal/), or a similarly permissive agreement, such as the Microsoft Open Specification Promise ( http://www.microsoft.com/Interop/osp/) or a Google-style patent license ( http://code.google.com/apis/gdata/patent-license.html). ... I realize that these are meaty (and potentially legally sensitive) questions of course, and likely ones that are not easily answered in a public forum. However, any feedback from the team would certainly be appreciated. The fact that people are even thinking about these types of questions is a good thing, both for open specification development in general, but also because it shows how successful and important the Twitter API is today. So again, continued success with the API, and I look forward to hearing more from the team. -DeWitt