Internet Law: Cases and Problems (Semaphore Press) (13th ed. 2023, annual editions 2011–)

Patterns of Information Law: Intellectual Property Done Right (2016) by-img

Open Source Property (2016) by-imgnc-img

Programming Languages and Law

The Structure and Legal Interpretation of Computer Programs, 1 Journal of Cross-Disciplinary Research in Computational Law no. 3, art. 19 (2023) by-img

Programming Languages and Law: A Research Agenda, 2nd ACM Symposium on Computer Science and Law 155 (2022) by-img


Data Property, 72 American University Law Review 829 (2023) (with Christina Mulligan) by-img

Chinese translation: 数据财产权, 9 法治社会 [Law-Based Society] 61 (魏远山 [Wei Yuanshan] trans. 2024)

A Programming Language for Future Interests, 24 Yale Journal of Law and Technology 75 (2022) (with Shrutarshi Basu, Nate Foster, Shan Parikh, and Ryan Richardson) by-img

Littleton: A Future Interests Interpreter (2022) by-img

Interactive Future Interests (2022) by-img

Property Conveyances as a Programming Language, in Proc. 2019 ACM SIGPLAN Int’l Symp. on New Ideas, New Paradigms, & Reflections on Programming and Software (Onward!) 128 (2019) (with Shrutarshi Basu and Nate Foster)

Real + Imaginary = Complex: Toward a Better Property Course, 66 Journal of Legal Education 930 (2017) by-img


Blockchains as Infrastructure and Semicommons, 64 William and Mary Law Review 1097 (2023) (with A. Jason Windawi) by-img

EIP-5218: NFT Rights Management (draft 2022) (with Yan Ji and Tyler Kell)

The Token-Bound NFT License (2022)

Copyright Vulnerabilities in NFTs, IC3 Blog (Mar. 21, 2022) (with Yan Ji and Tyler Kell) (also adapted for The Verge)

Design Choices for Central Bank Digital Currency: Policy and Technical Considerations (Brookings Institution 2020) (with Sarah Allen, Srdjan Capkun, Ittay Eyal, Giulia Fanti, Bryan Ford, Ari Juels, Kari Kostiainen, Sarah Meiklejohn, Andrew Miller, Eswar Prasad, Karl Wüst, and Fan Zhang)

All Smart Contracts Are Ambiguous, 2 Journal of Law and Innovation 1 (2019) by-img

Why Porn on the Blockchain Won’t Doom the Technology, Wired (Mar. 29, 2018) (with Arvind Narayanan and Kevin Werbach)

The Blockchain Gang, Slate (February 16, 2016) (with Arvind Narayanan)

Speech and Content Moderation

Brief of First Amendment and Internet Law Scholars as Amici Curiae, Moody v. NetChoice and NetChoice v. Paxton (U.S. 2023)

Content Moderation on End-to-End Encrypted Systems: A Legal Analysis, 8 Georgetown Law Technology Review 1 (2024) (with Charles Duan) by-img

An Economic Model of Intermediary Liability, 38 Berkeley Technology Law Journal 1011 (2023) (with Pengfei Zhang) by-img

Listeners’ Choices, 90 University of Colorado Law Review 365 (2019) by-img

Speech In, Speech Out, in Ronald K.L. Collins & David M. Skover, Robotica: Speech Rights and Artificial Intelligence 85 (2018) by-img

To Err is Platform, Knight First Amendment Institute Emerging Threats (2018) (responding to Olivier Sylvain, Discriminatory Designs on User Data, Knight First Amendment Institute Emerging Threats (2018)) by-img

The Platform is the Message, 2 Georgetown Law Technology Review 217 (2018) by-img

No ESC, The Recorder (Nov. 11, 2017) (part of a symposium on the 20th anniversary of Zeran v. AOL, and reprinted in Zeran v. Americal Online (Eric Goldman and Jeff Kosseff eds. 2020)) by-img

Anarchy, Status Updates, and Utopia, 35 Pace Law Review 135 (2014) by-img

The Virtues of Moderation, 17 Yale Journal of Law and Technology 42 (2015) by-img

The Illegal Process: Basic Problems in the Making and Application of Censorship 79 University of Chicago Law Review Dialogue 57 (2013) (responding to Derek E. Bambauer, Orwell’s Armchair, 79 University of Chicago Law Review 863 (2012)) by-img

Internet Regulation

Spyware vs. Spyware: Software Conflicts and User Autonomy, 16 Ohio State Technology Law Journal 25 (2020) by-img

Continuity and Change in Internet Law, Communications of the ACM, May 2019, at 24 by-img

Consenting to Computer Use, 84 George Washington Law Review 1500 (2016) by-img

Harry Potter and the Mysterious Defeat Device, Slate (September 22, 2015)

Death of a Data Haven: Cypherpunks, WikiLeaks, and the World’s Smallest Nation, Ars Technica (March 27, 2012)

Sealand, HavenCo, and the Rule of Law, 2012 University of Illinois Law Review 405 by-img

Dr. Generative or: How I Learned to Stop Worrying and Love the iPhone, 69 Maryland Law Review 910 (2010) (with Paul Ohm) (reviewing Jonathan Zittrain, The Future of the Internet–And How to Stop It (2008)) by-img

The Internet Is a Semicommons, 78 Fordham Law Review 2799 (2010) by-img

Owning the Stack: The Legal War to Control the Smartphone Platform, Ars Technica (Sept. 11, 2011)

Regulation by Software, 114 Yale Law Journal 1719 (2005) by-img

Seven Ways in Which Code Equals Law (with Cindy Cohn), in Code: The Language of Our Time (Christine Schipf et al. eds., Hatje Cantz 2003) by-imgnc-img

This essay is a slightly edited version of an address Cindy Cohn delivered at the Ars Electronica festival in 2003. It is available under a Creative Commons license thanks to generous permissions from her and from Ars Electronica.

Why The New York Times Might Win Its Copyright Lawsuit Against OpenAI, Ars Technica (Feb. 20, 2024)

Glimpse of the Future: AI in Hollywood, The Ankler (Feb. 7, 2023)

Computers and Robots Don’t Count, Slate (Aug. 23, 2016)

There’s No Such Thing as a Computer-Authored Work – And It’s a Good Thing, Too, 39 Columbia Journal of Law and the Arts 403 (2016) by-img

Copyright for Literate Robots, 101 Iowa Law Review 657 (2016) by-img

Indistinguishable from Magic: A Wizard’s Guide to Copyright and 3D Printing, 71 Washington and Lee Law Review 683 (2014) by-img

Brief of 36 Intellectual Property and Copyright Law Professors as Amici Curiae, ABC, Inc. v. Aereo, Inc. (U.S 2014) (with David Post)

Three Theories of Copyright in Ratings, 14 Vanderbilt Journal of Entertainment and Technology Law 851 (2012) by-img

Why Johnny Can’t Stream: How Video Copyright Went Insane, Ars Technica (August 30, 2012)

The Ethical Visions of Copyright Law, 77 Fordham Law Review 2005 (2009) by-img

Copyright, Technology, and Access to the Law: An Opinionated Primer (2008) by-img

Search Engines

Speech Engines, 98 Minnesota Law Review 868 (2014) by-img

What to Do About Google?, Communications of the ACM, September 2013, at 28 (draft PDF) by-img

Some Skepticism About Search Neutrality, in The Next Digital Decade: Essays on the Future of the Internet (Berin Szoka & Adam Marcus eds., TechFreedom 2010) by-img

The Google Dilemma, 53 New York Law School Law Review 939 (2009) by-img

Information Policy for the Library of Babel 3 Journal of Business and Technology Law 29 (2008) by-img

Don’t Censor Search 117 Yale Law Journal Pocket Part 48 (2007) by-img

The Structure of Search Engine Law, 93 Iowa Law Review 1 (2007) by-img

Privacy and AI

Report of the 1st Workshop on Generative AI and Law (2023) (with A. Feder Cooper, Katherine Lee, Daphne Ippolito, and 31 others) by-img

Incomprehensible Discrimination, 7 California Law Review Online 164 (2017) (responding to Solon Barocas and Andrew Selbst, Big Data’s Disparate Impact, 104 California Law Review 101 (2016)) (with Daniel Westreich) by-img

Big Data’s Other Privacy Problem, in Big Data, Big Challenges for Evidence-Based Policy Making 211 (Kumar Jayasuria & Kathryn Ritcheske eds., West Academic 2015) (page proof PDF)

The Law and Ethics of Experiments on Social Media Users, 13 Colorado Technology Law Journal 219 (2015) by-img

Do You Consent?, Slate (May 27, 2015)

First-Class Objects, 9 Journal on Telecommunications and High Technology Law 421 (2011) by-img

Known and Unknown, Property and Contract: Comments on Hoofnagle and Moringiello, 5 Brooklyn Journal of Corporate, Financial, and Commercial Law 85 (2011) by-img

The Privacy Virus, in Facebook and Philosphy (Dylan Wittkower ed., Open Court 2010)

Privacy as Product Safety, 26 Widener Law Journal 793 (2010) by-img

The Unmasking Option, 87 Denver University Law Review Online 23 (2010) by-img

Saving Facebook: A Response to Professor Freiwald, 95 Iowa Law Review Bulletin 13 (2009) by-img

Saving Facebook, 94 Iowa Law Review 1137 (2009) by-img

Total Information Awareness, The New Republic (online ed.) (Dec. 11, 2008)

Accidental Privacy Spills, Journal of Internet Law, July 2008, at 3 by-img

Google Books Settlement

The Orphan Wars, EDUCAUSE Review, Jan./Feb. 2011, at 48 by-img

The Elephantine Google Books Settlement, 58 Journal of the Copyright Society of the U.S.A. 497 (2011)

D Is for Digitize: An Introduction, 55 New York Law School Law Review 11 (2010) by-img

Filings for Amicus Curiae Institute for Information Law and Policy, Authors Guild v. Google Inc. (S.D.N.Y.)

Objections to the Google Books Settlement and Responses in the Amended Settlement

The Amended Google Books Settlement Is Still Exclusive, CPI Antitrust Journal (Jan. 2010) by-img

The Google Settlement: Why It Matters, Publishers Weekly (Nov. 23, 2009)

The Google Book Search Settlement: Ends, Means, and the Future of Books, American Constitution Society Issue Brief (Apr. 15, 2009) by-img

How to Fix the Google Book Search Settlement, Journal of Internet Law, April 2009, at 1 by-img

Civil Procedure

Brief of Amicus Curiae James Grimmelmann, Berry v. LexisNexis Risk & Information Analytics Group, Inc. (4th Cir. 2014)

Future Conduct and the Limits of Class-Action Settlements, 91 North Carolina Law Review 387 (2013) by-img

Brief of Amicus Curiae Electronic Frontier Foundation, OpenMind Solutions, Inc. v. Does 1-2925 (S.D. Ill. 2011) (with Julie Samuels)

Virtual Worlds

Bone Crusher 2.0: The Fourth Annual Greg Lastowka Memorial Lecture, 71 Rutgers University Law Review 843 (2019)

Virtual World Feudalism, 118 Yale Law Journal Pocket Part 126 (2009)

Virtual World Law in Busines and Legal Primer for Game Development (S. Gregory Boyd & Brian Green eds., Charles River Media 2006)

Virtual Power Politics in The State of Play: Law, Games, and Virtual Worlds (Jack M. Balkin & Beth S. Noveck eds., N.Y.U. Press 2006) (draft PDF) by-img

Virtual Borders: The Interdependence of Real and Virtual Worlds, First Monday (Feb. 2006) by-img

Virtual Worlds as Comparative Law, 49 New York Law School Law Review 147 (2004) by-img

Higher Education

When Tenure Standards Are Wrong 20 Green Bag 291 (2017) by-img

Scholars, Teachers, and Servants (2017) by-img

The Merchants of MOOCs, 44 Seton Hall Law Review 1035 (2014) by-img

SSRN Considered Harmful (2007) by-img

Jotwell Reviews

Words of Wisdom, Jotwell: Technology Law (June 2023), reviewing Samuel R. Bowman, Eight Things to Know About Large Language Models (draft 2023)

The Humble Vending Machine, Jotwell: Technology Law (July 2022), reviewing Gregory Klass, How to Interpret a Vending Machine: Smart Contracts and Contract Law (draft 2022) by-img

Content Cartels and Their Discontents, Jotwell: Technology Law (Apr. 2021), reviewing evelyn douek, The Rise of Content Cartels (Knight First Amendment Institute 2020) by-img

The Letter (and Emoji) of the Law, Jotwell: Technology Law (Apr. 2020), reviewing Eric Goldman, Emojis and the Law, 93 Wash. L. Rev. 1227 (2018) by-img

The Lolcat Theory of Internet Law, Jotwell: Technology Law (March 2019), reviewing An Xiao Mina, Memes to Movements (2019) by-img

Extraordinary Popular Delusions and the Madness of ICO Crowdfunding, Jotwell: Technology Law (November 2018) (reviewing Shaanan Cohney, David Hoffman, Jeremy Sklaroff, & David Wishnick, Coin-Operated Capitalism, (draft 2018) by-img

Make America Troll Again, Jotwell: Cyberlaw (April 2017) (reviewing Whitney Phillips, This Is Why We Can’t Have Nice Things: Mapping the Relationship Between Online Trolling and Mainstream Culture) by-img

Police Force, Jotwell: Cyberlaw (July 2016) (reviewing multiple articles) by-img

An Offer You Can’t Understand, Jotwell: Cyberlaw (May 2015) (reviewing Lauren E. Willis, Performance-Based Consumer Law, 82 University of Chicago Law Review (draft 2015)) by-img

Discrimination by Database, Jotwell: Cyberlaw (Nov. 2014) (reviewing Solon Barocas and Andrew Selbst, Big Data’s Disparate Impact (draft 2014)) by-img

The Cancer of the Internet, Jotwell: Cyberlaw (Nov. 2013) (reviewing Finn Brunton, Spam: A Shadow History of the Internet (2013)) by-img

If Code Is Law, Then Coders are Lawyers, Jotwell: Cyberlaw (Dec. 2012) (reviewing E. Gabriella Coleman, Coding Freedom: The Ethics and Aesthetics of Hacking (2012)) by-img

Undiplomatic Immunity, Jotwell: Cyberlaw (Nov. 2011) (reviewing Felix T. Wu, Collateral Censorship and the Limits of Intermediary Immunity, 87 Notre Dame Law Review 101 (2011)) by-img

Good Faith Scholarship, Jotwell: Cyberlaw (Oct. 2010) (reviewing Joseph Michael Reagle Jr., Good Faith Collaboration: The Culture of Wikipedia (2010)) by-img

Third Parties to the Rescue, Jotwell: Cyberlaw (Nov. 2009) (reviewing Michael Risch, Virtual Third Parties, 25 Santa Clara Computer & High Technology Law Journal 416 (2009)) by-img


Do the Right Thing, Communications of the ACM, May 2023, at 18 (with Kendra Albert) by-img

Renvoi and the Barber, 22 Green Bag 2d 109 (2019) by-img

Koans of Equity, 58 Journal of Legal Education 472 (2008) by-img

Cybercrime: Digital Cops in a Networked Environment (Jack M. Balkin, James Grimmelmann, Eddan Katz, Nimrod Kozlovski, Shlomit Wagman, and Tal Zarsky eds., N.Y.U. Press 2007)

Introduction: Books and Culture, in The Boy Who Could Change the World: The Writings of Aaron Swartz (New Press 2015) by-imgnc-imgsa-img

Modeling Facts, Culture, and Cognition in the Gun Debate, 18 Social Justice Research 283 (2005) (with Donald Braman and Dan M. Kahan)


Bunnies, Ducks, and One Great Dane, Killing The Buddha (Jan. 2002) by-img

Peer-to-Peer Terrorism, Salon (Sept. 26, 2001) by-img

From Each According to His IPO, Salon (Apr. 25, 2001) by-img

My Week, Grist Magazine (Oct. 2000) by-img

This series of diaries is available under a Creative Commons license through kind permission from Grist.

Quantum Computation: An Introduction (unpublished undergraduate thesis 1999) by-img

Elements of the Theory of Computation (2d ed.): Solutions Manual (Prentice-Hall 1999)

Please do not ask me for a copy. I do not own the copyright, and I am not in a position to verify teachers’ credentials. All inquiries should be directed to Prentice-Hall.

Finding Every Loophole, Harvard Crimson (Oct. 1, 1998)

Welcome to Microsoft: Here Be Dragons, Harvard Computer Review (Sept. 1997) by-img

Towards a More Flexible Core, Harvard Crimson (Apr. 10, 1997) (with Sarah Hurwitz and Benjamin Rahn)

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