OExchange is a specification for URL-based content sharing on the Web, introduced by a number of online service providers and social networking sites. The open link-sharing protocol has gained support from Google, Microsoft, LinkedIn, Digg, Instapaper, StumbleUpon, Clearspring Technologies and a handful more. "OExchange essentially establishes a common way for services like Posterous and Google Buzz to receive content. The protocol defines how 3rd-party tools, e.g. Clearspring's bookmarking and sharing service AddThis, can dynamically discover and share content to these services, as well as how sharing tools can read and set a user's sharing preferences." A number of these services, like Google Buzz and Instapaper, have already implemented the protocol, which together with others such as OpenID and OAuth intends to making sharing content on the Web completely open. OExchange is licensed under Open Web Foundation Agreement.
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