Nobel economist Joseph Stiglitz files amicus brief against OpenAI fair-use defence

What happened

On 30 October 2026, Professor Joseph Stiglitz filed a 51-page proposed amicus brief in support of the author and news plaintiffs in *In re OpenAI, Inc. Copyright Infringement Litigation*, No. 1:25-md-03143 (S.D.N.Y., Judge Sidney H. Stein), docket entry 2438-1. The brief addresses the parties' competing motions for summary judgment on fair use.

Who filed it

Stiglitz is a University Professor at Columbia University and was awarded the Nobel Memorial Prize in Economics in 2001 for his work on information economics. He served as chairman of President Clinton's Council of Economic Advisers and as senior vice president and chief economist of the World Bank. The brief states no party's counsel authored it and no party funded it.

What the brief argues

Drawing on his research on the information ecosystem, Stiglitz argues that courts should apply the fair-use doctrine sparingly in this setting. His central points, as set out in the brief's table of contents and argument headings, are that the fourth fair-use factor weighs decisively against OpenAI and Microsoft because AI-generated content substitutes for the plaintiffs' works; that the first factor also weighs against fair use because the defendants employ the plaintiffs' works for the same commercial purpose; and that the asserted public benefits do not justify the use because its net effect degrades the public's access to reliable information.

Status

This is a proposed amicus brief filed in support of the plaintiffs' motion for summary judgment. It is the filer's argument, not a court finding; the court has not ruled on the summary-judgment motions.