Hypothes.is

Hypothes.is is an open-source software project that aims to collect comments about statements made in any web-accessible content, and filter and rank those comments to assess each statement's credibility.

It has been summarized as "a peer review layer for the entire Internet."

Concept
The project is a system which allows annotation of web pages, using comments contributed by individuals and a reputation system for rating the comments. The plan is that the comments will be stored in the Internet Archive. Normal use is with a browser plug-in (Chrome) or a bookmarklet (others), and the plan is that links to specific comments will also be viewable without needing a plug-in.

People
The project is led by Dan Whaley, co-founder of GetThere, one of the first online travel booking systems in 1995. Its advisors have included John Perry Barlow, Charles Bazerman, Philip Bourne and Brewster Kahle.

Project
A Kickstarter drive to raise $100,000 to fund a working prototype narrowly reached its goal on November 13, 2011. The effort is organized as a non-profit. It has received financial support from the Shuttleworth Foundation, the Alfred P. Sloan Foundation, the Helmsley Trust, the Knight Foundation and the Andrew W. Mellon Foundation.

In December 2015, Hypothes.is was a founding member of a coalition of scholarly publishers, platforms, libraries, and technology organizations to create an open, interoperable annotation layer over their content.

In August 2022, after noting that being a nonprofit limited the company to grants and donations and with several of the key funding sources Hypothes.is relied on no longer available, they formed "Annotation Unlimited, PBC" (Anno). Anno is a public benefit corporation to house the Hypothes.is mission set up to allow investment. It attracted $14M seed round, including $2.5M from the provider of JSTOR.