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Google's moves to cram the top of its search results with more and more advertising is hammering the online travel industry, one of the company's biggest customers.
Expedia Group fell the most in 14 years on Thursday and TripAdvisor dropped the most in two years after the companies reported dismal third-quarter results and laid the blame on Google. Booking Holdings' shares dropped 8%, too, wiping out a combined market value of more than $13bn from the three online travel agents.
Google dominates the online search market, with at least three quarters of the market. People use the search engine to research trips, so for at least a decade, online travel agents have refined their websites with trustworthy content and easy booking tools to show up high in Google results.
This search engine optimisation (SEO), worked well until about five years ago. Around that time, Google began placing more ads on the top of search results, pushing down the free listings. The internet giant also built new travel search tools, which were mostly paid listings.