University of Chicago study finds sustainability reports swapped data for “puffery”
A University of Chicago Law School study of 15,000+ sustainability reports from 2,100+ firms found quantitative detail declined as “puffery” rose.
Photo by Jack Sparrow on Pexels
A working paper by University of Chicago Law School assistant professor Hajin Kim, published June 30, 2026 with co-authors Ningzi Li, Ronen Feldman, Yun Liu and Yuval Feldman, finds that corporate sustainability disclosures grew longer and more common after the 2015 Paris Agreement while their quantitative, verifiable content declined and vague promotional language increased. The paper, titled “What Sustainability Disclosures Disclose,” is Coase-Sandor Institute for Law & Economics Research Paper No. 26-7 and was posted to SSRN before being summarized on the Harvard Law School Forum on Corporate Governance on July 20, 2026.
The researchers used computational-linguistics methods to analyze more than 15,000 sustainability disclosures from over 2,100 firms spanning 1998 to 2023, according to the Harvard Law School Forum summary and independent coverage by ESG News. The paper builds sentence-level measures for traits that stakeholders are said to value in a disclosure: specificity, quantitative evidence, negative-news disclosure, and the presence of data tables or figures, alongside a measure of “puffery,” or vague promotional language.
What the sustainability disclosure puffery study found
The authors found that report volume and voluntary framework adoption, such as the Global Reporting Initiative (GRI) and the Sustainability Accounting Standards Board (SASB), surged in the years following the 2015 Paris Agreement. Over the same period, the density of quantitative and specific content declined while puffery language increased, the study concludes. The researchers describe this as reports becoming “less informative” as sustainability reporting became mainstream: “less specific and quantitative and included more fluff,” per the paper’s summary on the Harvard Law School Forum. The available public summaries of the study do not report an exact percentage for the increase in puffery or the decline in quantitative density; Winss was unable to verify a specific figure for either trend and does not cite one here.
| Study parameter | Detail |
|---|---|
| Disclosures analyzed | 15,000+ |
| Firms covered | 2,100+ |
| Date range | 1998-2023 |
| Method | Computational-linguistics / sentence-level text analysis |
| Key inflection point | Report volume and framework adoption rose after the 2015 Paris Agreement |
| Key finding | Quantitative/specific content declined as promotional “puffery” language rose |
| Framework stacking | More than 80% of 2022 GRI-aligned reports were also SASB-aligned |
The study also examined “framework stacking,” the practice of firms claiming alignment with multiple voluntary reporting standards at once. More than 80% of reports aligned with GRI in 2022 were also aligned with SASB, the authors found. Despite this overlap, the paper states there is “no consistent evidence that adopting a framework leads to improvement” on the quality dimensions the researchers measured, meaning firms that adopt more frameworks do not reliably produce more specific or quantitative disclosures as a result.
The authors frame the implication for policymakers and voluntary-standards bodies directly: “Voluntary regimes that want to move substance, not just adoption, may need firmer agreement on what specific, high-quality disclosure looks like, topic by topic,” they write, according to coverage of the paper.
The findings add data to a long-running debate over whether voluntary ESG reporting frameworks improve disclosure quality or simply proliferate paperwork. Winss has previously covered how to identify misleading environmental claims, commonly called greenwashing, and outlined six types of greenwashing companies use to mislead the public on sustainability. The University of Chicago-led study adds empirical, large-sample evidence to that pattern, while Winss’s own guide to sustainability report best practices lays out the kind of specific, quantitative disclosure the study finds in decline.
About the Coase-Sandor Institute for Law & Economics
The Coase-Sandor Institute for Law & Economics is a research institute at the University of Chicago Law School that publishes working papers on law-and-economics topics, including corporate governance, regulation and disclosure. Hajin Kim, the study’s lead author, is an assistant professor at the University of Chicago Law School whose research focuses on corporate and securities law. The paper “What Sustainability Disclosures Disclose” was released as Coase-Sandor Research Paper No. 26-7 on SSRN on June 30, 2026 and summarized on the Harvard Law School Forum on Corporate Governance on July 20, 2026, placing new large-sample evidence behind a debate over whether voluntary ESG reporting frameworks are improving disclosure quality or simply increasing its volume.
Sources: SSRN (University of Chicago Law School, Coase-Sandor Institute for Law & Economics); Harvard Law School Forum on Corporate Governance; ESG News
Featured image: photo by Jack Sparrow on Pexels (free Pexels license).
Become a Sponsor
Our website is the heart of the mission of WINSS – it’s where we share updates, publish research, highlight community impact, and connect with supporters around the world. To keep this essential platform running, updated, and accessible, we rely on the generosity of you, who believe in our work.
We offer the option to sponsor monthly, or just once choosing the amount of your choice. If you run a company, please contact us via info@winssolutions.org.
I specialize in sustainability education, curriculum co-creation, and early-stage project strategy. At WINSS, I craft articles on sustainability, transformative AI, and related topics. When I’m not writing, you’ll find me chasing the perfect sushi roll, exploring cities around the globe, or unwinding with my dog Puffy — the world’s most loyal sidekick.
