Hypothesis is a new effort to implement an old idea: a conversation layer over the entire web that works everywhere, without needing implementation by any underlying site.

Our team creates open source software, pushes for standards and fosters community.

Using annotation, we enable sentence-level note taking or critique on top of classroom reading, news, blogs, scientific articles, books, terms of service, ballot initiatives, legislation and more. Everything we build is guided by our principles of being free, open, neutral and lasting, to name a few.

Our efforts are based on the annotation standards for digital documents developed by the W3C Web Annotation Working Group. We are partnering broadly with developers, publishers, academic institutions, researchers, and individuals to develop a platform for the next generation of read-write web applications. You can follow our development progress on our roadmap. Many have contributed tools, plug-ins and integrations.

Recently, the Hypothesis team formed Anno, a public benefit corporation that shares the Hypothesis mission as well as its team. Anno will help scale Hypothesis in the higher education and research markets. The non-profit Hypothesis Project will continue to focus on advocacy, standards and the development of the larger paradigm of open annotation beyond our implementation.