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Prosecutors argue Google monopolized ad tech markets

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Google says it was not required to accommodate rival

services

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If found liable, Google could be ordered to sell Ad

Manager

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Publishers testified they could not feasibly switch from

Google

By Jody Godoy

Nov 25 (Reuters) - The U.S. Department of Justice will

make its final argument on Monday that Google illegally

dominated online advertising technology, seeking a second

antitrust win against the company.

The closing arguments in Alexandria, Virginia, cap a 15-day

trial held in September where prosecutors sought to show Google

monopolized markets for publisher ad servers and advertiser ad

networks, and tried to dominate the market for ad exchanges

which sit between buyers and sellers.

Google has argued prosecutors are bending U.S. antitrust law

to force it to accommodate competitors' services, and that the

case is focused on incidents from years past when Google was

still building and improving its offerings.

Publishers testified at trial that they could not switch

away from Google, even when it rolled out features they

disliked, since there was no other way to access the huge

advertising demand within Google's ad network.

News Corp ( NWSA ) in 2017 estimated losing at least $9

million in ad revenue that year if it had switched away, one

witness said.

If U.S. District Judge Leonie Brinkema finds that Google

broke the law, she would consider prosecutors' request to make

Google at least sell off Google Ad Manager, a platform that

includes the company's publisher ad server and its ad exchange.

Google offered to sell the ad exchange this year to end an

EU antitrust investigation but European publishers rejected the

proposal as insufficient, Reuters first reported in September.

Analysts view the ad tech case as a smaller financial risk

than the case where a judge ruled Google maintains an illegal

monopoly in online search, and where prosecutors have argued the

company must be forced to sell its Chrome browser.