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Tommaso Valletti

@tomvalletti.bsky.social

770 followers 46 following 25 posts

econ professor imperial college london https://profiles.imperial.ac.uk/t.valletti

Tommaso M. Valletti is Professor of Economics at Imperial College Business School, and also Professor of Economics at the University of Rome Tor Vergata (Italy). He is a Fellow of CEPR. He is a Non-Executive Director to the board of the UK's Payment Systems Regulator. .. more

Economics 37%

Business 36%

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Reposted by Tommaso Valletti

Reposted by Mouin Rabbani, Vali Nasr, Tommaso Valletti , and 4 more Mouin Rabbani, Vali Nasr, Tommaso Valletti, Jayati Ghosh, Andrea Roventini, Hugo Ñopo, Trudy Harpham

Reposted by Tommaso Valletti, Thom Brooks

Tommaso Valletti @tomvalletti.bsky.social · Aug 18

Once properly interpreted, econ theory overwhelmingly supports the ITOH.

👉 Without synergies/spillovers, mergers harm consumers.

So: weakening merger control in the name of innovation is misguided.
The economics is clear — the ITOH still stands.

📄 Article www.sciencedirect.com/science/arti...

The innovation theory of harm in merger control: Some clarifications

Recent literature has analyzed the unilateral effects of mergers on investment and innovation. This note explores the Innovation Theory of Harm from a…

www.sciencedirect.com

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Tommaso Valletti @tomvalletti.bsky.social · Aug 18

My paper revisits the Innovation Theory of Harm (ITOH): mergers can reduce firms’ incentives to invest & innovate.

This theory has shaped major EU merger cases in telecoms & agro-chemicals.

What I find:

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Tommaso Valletti @tomvalletti.bsky.social · Aug 18

🚨 New paper in Economics Letters!

Do mergers boost or harm innovation? The debate is heating up in EU & UK policy circles.

Some argue:
Relax merger control → more investment, productivity, competitiveness.
This view has influenced reports like Draghi’s & UK gov’t policy.
But is it right? 🤔

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Reposted by Tommaso Valletti, Robert Metcalfe

Diane Coyle @dianecoyle1859.bsky.social · Jul 25

Call for papers, 4th UK Workshop on Digital Economics, London 28 November 2025: competitionpolicy.ac.uk/events/4th-w... This is always a great event

Centre for Competition Policy

High quality independent research into competition policy and regulation

competitionpolicy.ac.uk

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Reposted by Nando Sigona, Ruth Mace, Tommaso Valletti

Reposted by Alex Coad, Tommaso Valletti, Robert Metcalfe

Brett Hollenbeck @bretthollenbeck.com · Jul 11

🚨Free data alert!! 🚨 Please share.

Large new dataset of Amazon product reviews, including full text and photos and product characteristics, with individual *reviews labeled as fake reviews*.

I believe this is the first publicly available data of this kind.

github.com/bretthollenb...

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Tommaso Valletti @tomvalletti.bsky.social · Jul 1

Findings: Ex post actions against consummated mergers exist but do not have a good record of success.

Implications: postmerger policy ineffectiveness needs a more stringent ex ante policy in order to achieve the right balance.

Link to the pre-print:

papers.ssrn.com/sol3/papers....

Ciao

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Tommaso Valletti @tomvalletti.bsky.social · Jul 1

New paper just accepted in the Antitrust Law Journal written with John Kwoka.

We study the policy toward consummated mergers that prove to be anticompetitive, both in theoretical and empirical terms.

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Reposted by Tommaso Valletti

Reposted by Tommaso Valletti, Tomaso Duso

Centre for Economic Policy Research @cepr.org · Jun 16

⭐Join us online for a high-level debate on merger control in Europe
Featuring E Tarantino, S Athey, @janeeckhout.bsky.social, P Heidhues, F Ederer, @tomasoduso.bsky.social
Moderator: @cristinacaffarra.bsky.social
14 July @ 17:00 CEST
cepr.org/events/updat...
@tomvalletti.bsky.social

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Tommaso Valletti @tomvalletti.bsky.social · May 15

I’ve written this piece in The Times.

Competition should work for the many, not the few.

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Reposted by Tommaso Valletti

Tommaso Valletti @tomvalletti.bsky.social · Apr 16

Video of this remarkable webinar now available online:
www.youtube.com/watch?v=v7e5...

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Reposted by Tommaso Valletti

Centre for Economic Policy Research @cepr.org · Mar 28

Designing “Buy European” Policies for European Strategic Autonomy - 15 Apr @ 17:00 CEST

🗣️@snoep.bsky.social, D Harhoff, U Akcigit, G Spagnolo, B Baltzan, @schularick.bsky.social

@sandertordoir.bsky.social @tomvalletti.bsky.social @cristinacaffarra.bsky.social

cepr.org/events/desig...
#EconSky

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Tommaso Valletti @tomvalletti.bsky.social · Mar 21

FBP muted price competition among bookshops. But competition was still at work and turned to non-price aspects that overall have benefited readers in the Italian book market.

The paper is dedicated to Mario a dear friend who passed away far too soon. ❤️

Read at: ow.ly/BnZQ50VkExP

Ciao/Fin

Cultural exception? The impact of price regulation on prices and variety in the market for books

Fixed book price (FBP) agreements are a form of resale price maintenance applied to books in various countries. FBP restricts retail price competition with the aim of promoting book production variety. Yet, despite its popularity and adoption in many countries, there is no empirical evidence on its effects. We offer systematic evidence on the impact of FBP on book variety and prices using a detailed new dataset from Italy that includes the universe of books published and bought, before and after the introduction of FBP. Our results indicate that FBP raises prices without significantly affecting the number of new books published in the marketplace. However, it also increases considerably the variety of books actually bought, especially from independent bookstores. We estimate a structural model of demand that accounts for both effects, finding that consumers overall benefited from the regulation.

ow.ly

Tommaso Valletti @tomvalletti.bsky.social · Mar 21

We also find that employment increased, and used LLM to look at Google reviews & ratings about bookshops.

Readers appreciate discovery, suggestions & events organized by bookshops. This is in line with the “service effort” mechanism in settings where otherwise there would be free-riding. 5/

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Tommaso Valletti @tomvalletti.bsky.social · Mar 21

Not really. We also find that the *variety* of books purchased by readers went up. Books that had a near-zero market share before FBP... started being purchased afterwards.

So there is a possible trade-off! 4/

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Tommaso Valletti @tomvalletti.bsky.social · Mar 21

Indeed, comparing with the same Italian books sold in Switzerland at the time (Italian is an official language there too! And there is no regulation of books in CH), final prices to readers went up, especially among independent bookshops that are very common in ITA.

End of the story? 3/

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