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Harvard's Groundbreaking Project Documenting Online Content Removals Changes Name to Lumen, Reflecting Expanded Mission and International Scope

Harvard University’s Berkman Center for Internet & Society is pleased to announce exciting changes to our pioneering Chilling Effects project, including an expanded mission and a new set of international research partnerships. To better reflect this evolution in scope as well as the changes in the landscape over the fourteen years since it was launched, the project has changed its name to “Lumen,” and can be found at The name borrows from the unit of measurement for visible light, highlighting the use of data for transparency reporting.

“Since Chilling Effects was founded in the wake of the passage of the US Digital Millennium Copyright Act, the project has been essential to the collection and study of notices sent to online platforms requesting the removal of content,” said Chris Bavitz, Faculty Co-Director of the Berkman Center and Clinical Professor of Law at Harvard Law School. “We are excited for Lumen to continue this important work with an expanded scope, in partnership with a collection of extraordinary institutions.”

Started in 2001 by then-Berkman fellow Wendy Seltzer and current Berkman Faculty Director Jonathan Zittrain, Chilling Effects was founded to provide a database of requests for content removal, to assist scholars and others in understanding trends in content removal demands and practices, and to facilitate research into how online intermediaries make their content removal decisions.

“Both the variety of online communications and the range of takedown demands have grown enormously since we started transparency reporting with Chilling Effects in 2001,” said Wendy Seltzer, now a member of the Berkman Center's Fellowship Advisory Board, “The new Lumen partnerships will enable us to shed light on takedown claims and responses around the world, further supporting academic research and news reporting on the climate for online expression. I look forward to its next decade.”

Over time, the project has expanded in the types of notices it hosts, the sources they come from, and the sheer volume of requests it receives. In addition to DMCA notices, request types now include removal demands grounded in trademark, patent, locally-regulated content, and private information removal claims. Companies sharing notices they receive include Google, Twitter, Wikipedia, WordPress, and Reddit. The number of notices collected has grown from a few notices per week, to approximately 4,000 per day. As of July 2015, the Chilling Effects database contains more than three million notices and is the definitive source for online content removal requests.

“While people may differ about the wisdom of censorship in one case or another, it shouldn’t take place secretly,” said Jonathan Zittrain, Faculty Director of the Berkman Center and George Bemis Professor of International Law. “Lumen stands for the proposition that demands for online redaction should be available for study, so that we can know the shape of what we are not seeing, whether the elisions are caused by a government or by a private party.”

Central to the project’s expanded mission are new partnerships with three top international research centers who share the Berkman Center’s commitment to illuminating the actions, issues, and complexities within today’s online content ecosystem. These centers will serve as regional hubs for Lumen’s activities around the world: the Nexa Center for Internet & Society in Turin, Italy; the Instituto de Tecnologia & Sociedade in Rio de Janeiro, Brazil; and the Center for Communication Governance in Delhi, India. These partnerships will enable Lumen to map and facilitate research on requests to remove content from the Internet at a global level, an important development as takedown requests increasingly have global applications and potential reach.   

“The removal request landscape in the US has evolved considerably over the last decade-and-half,” said Urs Gasser, Executive Director of the Berkman Center and Professor of Practice at HLS. “Globally, it has become even more complex. We are particularly excited about leveraging the power of our international research partnerships as we seek to develop the most accurate picture possible of what content is or is not available to the public and why.”

"Increasing the transparency of Internet takedowns is essential to ensure the appropriate level of awareness in policy-makers and in the public at large,” said Juan Carlos de Martin of the Nexa Center. “We are therefore glad to participate in this exciting project and to contribute to the understanding of takedown trends and actions in Europe".

"We're delighted to be a part of Lumen,” said Chinmayi Arun of the Center for Communication Governance. “We look forward to tracking and analysing the takedown regime in India, and to working on our findings with researchers around the world. We welcome this opportunity and thank the Berkman Center for opening Lumen to us.”

The Lumen database is one of a suite of initiatives of the Berkman Center focused on preserving access to information and mapping speech and data flows online. Other projects include Internet Monitor, which aims to evaluate, describe, and summarize the means, mechanisms, and extent of Internet content controls and Internet activity around the world;, a server-side plugin to keep links working on blogs and websites; and Herdict, a tool that collects and disseminates real-­time, crowdsourced information about Internet filtering, denial of service attacks, and other blockages.

For more information about updates to the Lumen project and its international partners, please see

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About Lumen
Lumen is an independent research project studying cease and desist letters concerning online content. We collect and analyze requests for removal of online content. Our goals are to educate the public, to facilitate research about the different kinds of complaints and requests for removal--both legitimate and questionable--that are being sent to Internet publishers and service providers, and to provide as much transparency as possible about the “ecology” of such notices, who is sending them and why, and to what effect.

About the Berkman Center for Internet & Society
Founded in 1997, the Berkman Center for Internet & Society at Harvard University is dedicated to exploring, understanding, and shaping the development of the digitally-networked environment. A diverse, interdisciplinary community of scholars, practitioners, technologists, policy experts, and advocates, we seek to tackle the most important challenges of the digital age while keeping a focus on tangible real-world impact in the public interest. Our faculty, fellows, staff and affiliates conduct research, build tools and platforms, educate others, form bridges and facilitate dialogue across and among diverse communities. More information at