There is more research to do. Even now, we have only a handful of studies, and most of those use US data. This is one area that “more is better” and I am excited to keep learning and updating beliefs. Much gratitude for all engaged in the endeavor.  12/N

But the literature does not establish that any Rise of Market Power is due to a failure of previous enforcement regimes, at least for the broadest trends. Of course, we can always learn more and that learning can (and should) guide enforcement.   11/N

What about antitrust enforcement? Technology change can make enforcement more important—for example if it shifts to higher fixed costs / lower marginal cost. And aggressive enforcement has been impactful in many of the “model industries.”   10/N

And then there is the graph on worldwide GDP over time from “Our World In Data” that puts where we are economically in better perspective than anything else I’ve seen. What a ride we are on!   9/N

Most of the studies rely on structural modeling. Can we corroborate them? Maybe so. Conlon et al (2023) show that DLEU markup changes are uncorrelated with price changes over 1980-2018. Lower costs may explain any markup growth.  8/N

Each of these industry studies stands on its own and makes a significant contribution. But by putting them together can we learn even more?  I think maybe so. Based on my interpretations, I produce the following table:      6/N

 So how can mainstream IO contribute? One way is industry studies with long time horizons. And we have a set of articles and working papers now, in our “model industries” that we know so well: consumer products, cement, wholesaling, steel, autos, airlines.  5/N

But with great influence comes great scrutiny. I characterize methodological concerns surrounding DLEU, which fall loosely into three buckets. My ultimate interpretation is that DLEU raises important questions, and has forced IO to think bigger. A big service for the field.    4/N

A natural starting point is De Loecker, Eeckhout, Unger (2020, QJE) [DLEU], which estimates rising markups in the US over the last ~four decades. An explosive result that has greatly impacted research and policy.  3/N

By “The Rise of Market Power,” I mean the economics literature that explores concentration and markups over time. An incredible number of scholars have contributed ideas and evidence here, too many to tag. What do we now know?   2/N

I'm looking forward to the UZH Market Power Workshop. My talk is "Industrial Organization and the Rise of Market Power." It will cover 8 IO studies on specific industries over long time horizons, with the goal of identifying commonalities and understanding differences. Hope to see some of you there.