My thesis is that Booking.com (BKNG) was able to grow throughout Europe because Priceline didn't listen to the "experts" and force a change from the agency model to the merchant model. Meanwhile, Expedia (EXPE) was attached to the merchant model that worked well in the U.S. but they were too slow in recognizing differences in European markets.

The Oral History of Travel's Greatest Acquisition by Dennis Schaal is a must-read for long-term Booking Holdings investors. It shows why the acquisitions of Active Hotels and Bookings were fantastic and it lays down the groundwork as to why Booking.com was able to dominate the European OTA landscape. We cite the document heavily referring to it as Booking.com's Oral History.

Revenue and gross booking numbers are from 10-K filings for Booking Holdings and Expedia Group.

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