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Lumen collects and studies online content removal requests, providing transparency and supporting analysis of the Web’s takedown “ecology,” in terms of who sends requests, why, and to what ends. Lumen seeks to facilitate research about different kinds of complaints and requests for removal – legitimate and questionable – that are being sent to Internet publishers, platforms, and service providers and, ultimately, to educate the public about the dynamics of this aspect of online participatory culture.

Conceived and developed in 2002 by then-Berkman Center Fellow Wendy Seltzer, Lumen (until recently known as Chilling Effects) was nurtured with help from law school clinics at Berkeley, Stanford, University of San Francisco, University of Maine, George Washington School of Law, Santa Clara University School of Law, and Harvard Law School’s Cyberlaw Clinic (based at the Berkman Klein Center).

Initially focused on requests submitted under the United States’ Digital Millennium Copyright Act, Lumen now includes complaints of all varieties, including those concerning trademark, defamation, and privacy, both domestic and international.  Currently, the Lumen database contains millions of removal requests, and grows by more than 20,000 notices per week, from companies such as Google, Twitter, YouTube, Wikipedia, Reddit, Medium, Github, Vimeo, and Wordpress. Because of recent dramatic increases in notice volume, in 2014 the project upgraded to a more robust, scalable website that provides more granular data and API access for notice submitters and researchers.

Our Work 18

Nov 14, 2022

BKC Comment to the FTC on Transparency and Commercial Surveillance

On behalf of BKC and its projects and associates, the Cyberlaw Clinic submitted a comment regarding the FTC's ANPR related to commercial surveillance and data privacy.

Jul 21, 2022

Toward Best Practices around Online Content Removal Requests

Recap and resources from the Lumen/BKC "Takedowns and Transparency" research sprint...

Mar 3, 2022

Lumen Database Leads Research Sprint Exploring Best Practices For Transparency around Online Content Takedowns

Global cohort of scholars, professionals, and civil society representatives consider norms and regulations for removal of online content

BKC's Lumen Database is launching nine-week “Takedowns and Transparency Research Sprint"...

Event Series

Researching with the Lumen Database: Q&A Sessions: Jan 18 / Jan 25 / Feb 1 / Feb 8

Lumen is hosting a series of weekly sessions every Tuesday for potential researchers interested in working with the database.

Feb 12, 2021

Prediction from Lumen Database researchers cited by Vice

A new video shows Beverly Hills cops playing the Beatles to trigger Instagram's algorithmic copyright filter, raising concerns that some law enforcement are using copyright…

May 15, 2020

Lumen database enables Wall Street Journal investigation

Removal request data from Google uncovers false takedown claims

The WSJ collaborated with Lumen, exploring its database of copyright removal notices and uncovering false takedown claims to Google.

Dec 19, 2019

Lumen Comments on Copyright and Transparency for EU Meeting

Christopher Bavitz and Adam Holland joined an EU meeting to discuss the importance of data transparency in takedown regimes and key learnings from the Lumen Database. 

Nov 12, 2019

Illuminating the Flows – and Redactions – of Content Online

Arcadia to support expansion of Harvard’s Berkman Klein Center Lumen Database

Arcadia to support the expansion of Lumen Database

ECT News Network
Jan 23, 2019

Dutch Doc Wins 'Forget My Suspension' Case

Google must remove search results about medical regulators' conditional suspension of a Dutch physician in the first "right to be forgotten" case of its kind in the European Union.

Aug 13, 2018

How Turkey silences journalists online, one removal request at a time

Ahmed Zidan references Lumen database in article connected to censorship and journalism in Turkey.

May 7, 2018

Your Guide to BKC@RightsCon 2018

Connect with members of the Berkman Klein community and learn about their research.

Apr 9, 2018 @ 12:00 PM

Remedies for Cyber Defamation

Criminal Libel, Anti-Speech Injunctions, Forgeries, Frauds, and More

“Cheap speech” has massively increased ordinary people’s access to mass communications -- both for good and for ill. How has the system of remedies for defamatory, privacy…

Apr 14, 2016

Cyberlaw Clinic and Lumen Project Reps Contribute to Section 512 Study

On April 1st, the Copyright Office closed the initial comment period for a public study undertaken to evaluate the impact and effectiveness of the Digital Millennium…

Feb 15, 2011

Questions for Secretary Clinton concerning "Internet freedom"

Faculty associate Matthew Hindman provoked an energetic email exchange among members of the extended Berkman Center community today, in anticipation of Secretary Clinton's …

Mar 6, 2009

Debating CDA 230

An exchange between John Palfrey and Adam Thierer concerning tweaking Section 230 of the Communications Decency Act was published today in Ars Technica...

Oct 29, 2008

Global Network Initiative launches

Berkman is pleased to announce the launch of the Global Network Initiative, a dynamic effort developed in partnership with leading human rights groups, academics, socially…

Aug 29, 2008

New opportunities with Berkman Center friends

The UC Berkeley School of Law is seeking a clinical professor to serve as the director of the Samuelson Law, Technology and Public Policy Clinic. And Stanford Law School has…

Apr 17, 2007 @ 12:30 PM

Sacked by Copyright: DMCA Takedowns and Free Expression

Wendy Seltzer, Berkman Fellow

Wendy Seltzer, founder of Chilling Effects, discussed "Sacked by Copyright: DMCA Takedowns and Free Expression."

Community 10

Centro LatinoAmericano de Investigación Periodística

Clean Slate: how felons are erasing compromising news online

The Lumen database received a shoutout apropros the "back-dated article technique" whereby individuals, often using false credentials, are able to initiate takedown requests of…

Aug 4, 2023
The Washington Post

Elon Musk’s Twitter is helping governments shut their citizens up

Rest of World, a nonprofit publication that covers global technology, utilized the Lumen Database in their investigation into Twitter's takedown practices following Elon Musk's…

May 2, 2023

​Apple’s proposed new child safety features and the problems with privacy tradeoffs

Shreya Tewari shares the problems with proposals that compromise user privacy in favor of other important goals.

Sep 9, 2021
BKC Medium Collection

Lumen — The Year in Review

The Lumen project’s annual report highlights the technical improvements, research, outreach, and data collection from the last year.

Oct 14, 2020

Twitter Deletes Trump’s Photo of Himself After NY Times Copyright Complaint

Lumen database hosts DMCA notice for the tweet

Jul 2, 2020

A German company is responsible for the deletion of videos critical of the Albanian government

Searches in the Lumen database reveal the complexities around the rules that platforms follow when they agree to the removal of content

Mar 19, 2020
Harvard Law Today

Shedding light on fraudulent takedown notices

Berkman Klein Center’s Lumen database helps bring attention to falsified court orders

Dec 13, 2019
Committee to Protect Journalists

India uses opaque legal process to suppress Kashmiri journalism, commentary on Twitter

The Committee to Protect Journalists used Lumen in an investigation of Indian government censorship of Kashmiri journalism.

Oct 24, 2019
The New York Times

Even Trump Can’t Turn Down a Nickelback Joke (but Twitter Did)

Lumen shows why Twitter took down a video posted by President Trump

Oct 3, 2019

People 05

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