Common Ownership & Employee Earnings updated & improved Consider a pair of companies that sell into the same product market. If pair shares common owners, the owners have incentive for pair to soften competition. Same with local labor market competition papers.ssrn.com/sol3/papers....

The AEA released the committee's report on the 2023 climate survey and it's chock full of depressing stuff, but I couldn't help but notice this pull quote. Posted here without further commentary. 👀

We usually rely on GDP, trade, or wages to study the past. This amazing paper flips the script. It analyzes 630,000 paintings (1400-2000) to extract emotions and shows how art tracks living standards, wars, inequality, and even climate shocks. (How is this economics? Everything is economics!)

Nascent competition, killer acquisitions, acquihires — join Meghan Rissmiller, Michaela Spero, Rahul Rao, and me for an American Bar Association Antitrust seminar on how innovation competition should be accounted for in merger control. September 10 12-1pm www.americanbar.org/events-cle/m...

Great in-depth piece on the Texas v. BlackRock common ownership lawsuit www.mlex.com/mlex/article...

Who is Maurice R. Greenberg?!?

More evidence of market / power concentration, cc @helenamalikova.bsky.social via @conjugateprior.org who recommends @florianederer.bsky.social as a follow. From the funders' perspective, it's a lot easier to "cash in" via a sale, so how can governments encourage them to accept the risk of an IPO?

How can tariffs improve welfare? Your country needs market power. A quick explainer below 👇🏻

I'm so excited to see this paper coming out in RESTUD. Fun facts about this paper: 1) My amazing co-author Bruno and I had never met in person until after we completed the first draft. 2) It's my first and only paper that was never rejected by a journal. 3) I can now claim to understand macro.

I do not like this trend. From "The Great Start-up Sellout and the Rise of Oligopoly" by @florianederer.bsky.social and Bruno Pellegrino. florianederer.github.io/startups_P&P...

"Common ownership grew dramatically in the US economy from 1995 to 2021. It could raise producer profits at the expense of consumer surplus & lead to a substantial deadweight loss." Recently accepted paper by @florianederer.bsky.social & Pellegrino: www.restud.com/a-tale-of-tw... #econsky #REStud

I was thrilled to join Emanuele Tarantino, Susan Athey, Cristina Caffarra & others for CEPR’s webinar on “Updating Merger Control as an Economic Policy Tool for Europe?” How can merger policy adapt to support innovation, growth & strategic autonomy? 📺: youtu.be/CO_IJhFczCk

Common ownership has risen globally since 2005—especially among large firms—driven by the broad, overlapping portfolios of the Big Three (BlackRock, Vanguard, and State Street) asset management firms, from Antón, @florianederer.bsky.social, Giné, and Ramirez-Chiang https://www.nber.org/papers/w33965

Happy 4th of July to you all! 🇺🇸🎹🎶🎆

All posts critical of Yale Law School are hereby suspended.

🚨New Working Paper🚨 "Common Ownership Around the World"📈🌍 We analyze common ownership in 49 countries from 2005 to 2019 and show that it is widespread and rising globally.

Alright, I've peaked. It's only downhill from here.

"But how is this economics?" www.thepeakmagazine.com.sg/influence/it...

The past really sticks. Even after 4 generations, your great-grandfather’s economic status still largely shapes your own. 👉 33% persistence across time for whites 👉 But racial inequality is the key driver The American Dream? More inherited than we thought. www.nber.org/papers/w33923

AI + social media = polarization machine 🧠📱 Recommender systems trap users in echo chambers and ad-based platforms profit from partisan division. www.nber.org/papers/w33892

Koijen & Yogo's (2019) demand system approach transformed asset pricing by linking portfolio data to demand elasticities. But why are estimated elasticities so low (around 1) when classical models say they should be much higher? Enter Fuchs, Fukuda & Neuhann (2025)

🚨 BlackRock, Vanguard & State Street are being sued for allegedly colluding to cut coal output via ESG. The case tests the common ownership theory and a win "would embolden and encourage others to bring similar lawsuits." Big case. Big implications. www.bloomberg.com/news/article...

Why do dictators target the socially isolated? 📢 New theory by @ksonin.bsky.social: Propaganda works best when people are either totally atomized or tightly unified rather than in between. 🎯 Optimal strategy? Don’t focus on influencers. Target the fringes of the network.

The #MeToo movement led to a 10% jump in sex crime reports and the effect lasted over 2 years. ✅ More reporting ✅ More arrests ❌ Not just more crimes ✅ Impact across race & income Social movements can change high-stakes behavior. papers.ssrn.com/sol3/papers....

Common leadership (two firms sharing executives or board directors) contributes to collusion. Collusion probability between two firms increases by 12 percentage points after the onset of common leadership, compared to only 1.2 percent in the absence of common leaders. www.nber.org/papers/w33866

"Boomers without Borders" would be an amazing title for this paper. Portugal quadrupled its number of foreign retirees by offering them 10 years of income tax-free retirement. Some countries (e.g., Finland) responded by taxing pensions at the source.

Harvard Business School has removed Francesca Gino from its website. Her profile was up as recently as May 13 but is now gone. web.archive.org/web/20250513...

🚨 High-speed internet is hurting teen mental health, especially girls. More screen time Less sleep Less studying Less real-life socializing And when they're distressed they go online, not offline. www.sciencedirect.com/science/arti...

🚨 DOJ & FTC just weighed in on common ownership: ✅ Passive index investing? Protected. ✅ Shareholder advocacy? Protected. ❌ Using stakes in competitors to cut output across an industry? Not protected. Antitrust safe harbors don't shield anticompetitive common ownership.

Political advertising on Facebook and Instagram before the 2020 US election had no effect. www.nber.org/papers/w33818

LLM adoption boosts the quantity of scientific papers that researchers write by 25.7-89.3%, with the strongest quantity effects for East Asian scholars and in the social sciences. But the papers are worse. Another quantity-quality tradeoff! yianyin.net/index.html

Do Private Equity and Other Investors Harm Competition in the Pharmaceutical Industry? Common ownership among rivals and “rollup” deals of smaller pharmaceutical firms by private equity provide strong reasons for antitrust authorities to increase their scrutiny. www.promarket.org/2025/05/15/d...

A new study with almost 300 Chinese student subjects replicated the main findings of our Management Science paper (Ederer & Manso 2013) that short-term pay-for-performance and lack of tolerance for early failure inhibit innovation. So happy to see this experiment still making waves!

The Journal of Economic Literature has a book review of @aedmans.bsky.social's excellent book "May Contain Lies" ... ... but I'm ever so slightly disappointed that it does not discuss the most important part of the book. 😂

One last research lunch with my amazing PhD student @asil_aslihan before she's off to her new job as law professor at @DukeLaw! Advising her was an immense privilege because her work brilliantly combines industrial organization, antitrust, and legal scholarship.

This graph by my colleague Tim Simcoe might be the most important one in recent US business history. It's a key reason why the DOJ won the Google adtech case. Google's average impressions are so much greater than its nearest rivals that Google appears as a statistical outlier.

This is an incredibly important paper. If you're an antitrust scholar and you're getting paid hundreds of thousands of dollars by a dominant monopolist as expert witness in a lawsuit that's in your research area, shouldn't you disclose that work on your CV? www.nber.org/papers/w3364...

The DOJ is pushing for a breakup of Google's adtech business, specifically calling for the separation of AdX, Google’s ad exchange platform. The process would be managed by a divestiture trustee, with the government retaining the authority to approve or reject any proposed buyer.

One day I won't have to wait up till nearly midnight for antitrust court filings. But today is not that day.

Found my Halloween costume according to @florianederer.bsky.social

I also got a plaque on Wednesday. #twoforone

Pharmacy chains like CVS are putting national-brand products behind plexiglass and are leaving the cheaper CVS-branded versions out in the open, right next to them. Is this just a shrinkage deterrent or a clever nudge to boost high-margin house brands?

Back at it

I'm delighted to receive the BU Questrom 2025 MBA Core Faculty Award ... ... all thanks to my amazing TA Nicole Zeller who was also honored in today's ceremony.

Jon Levin, the current Stanford President, was an advisee of Paul Klemperer at Nuffield College. Mark Carney, the current and likely future Prime Minister of Canada, was an advisee of Meg Meyer at Nuffield College. Meg and Paul are my favorite economics power couple.

There already exists a published paper!

Could we please stop trying to make #antitrust fit some ideology and just focus on making markets work? #competition #markets #economics #econsky

Does an NBER paper released in a week in which there are fewer other NBER working papers have better outcomes (e.g., more downloads, more citations, ...)? @paulgp.com

Temporary tariffs cause a recession. www.nber.org/papers/w33726

Education widens the financial literacy gap between men and women. Women's financial literacy plateaus after college — men's keeps rising. drive.google.com/file/d/1Uh5V...