By Natalia Drozdiak in Brussels and Sam Schechner in Paris

Alphabet Inc.'s Google Thursday hit back at European Union accusations that it abuses its dominant position with its shopping and advertising services, ramping up its fight back against the bloc's regulators.

The European Commission, the bloc's antitrust regulator, has had Google under its microscope for years over concerns the search giant abuses its dominance and has shut out rivals in various markets. The continuing probe has already led to formal charges aimed at several of Google's business practices, potentially exposing Google to billions of euros in fines and demands that it overhaul its operations.

On Thursday, Google again defended the way it places retailers' ads for products on some of its search results by saying there is no evidence that those ads hurt price-comparison websites. The company contends that the commission looked at too small a set of rival sites, and argues that on mobile devices most people shop with dedicated apps anyway.

"The Commission's revised case still rests on a theory that doesn't fit the reality of how most people shop online," said Kent Walker, Google's general counsel, in a blog post dedicated primarily to the company's response to the EU's shopping charges.

Google last year rebuffed the EU's first set of shopping charges, saying the commission failed to take into account the fast growth of companies like Amazon.com Inc. and eBay Inc.

The commission circled back this July with an extra layer of charges inthe shopping case, sharpening its argument that Google's comparison shopping service operates in a market separate from those e-commerce platforms--an argument Google again rejected. In separate charges, the EU in July also accused Google of breaching EU antitrust rules by restricting how a website that offers a Google search function can show advertisements sold by other companies.

In response to the EU's shopping charges, Google said it rejects the commission's proposed solution of providing what the company called subsidized advertising space for price-comparison sites, instead of the retailer ads that Google's usually shows.

Forcing Google to place competitors' product ads in its search results "would just subsidize sites that have become less useful for consumers," Mr. Walker said.

In the advertising case, Google argues its AdSense for Search business has always faced competition from rivals like Microsoft Corp. The company also said that it phased out complete exclusivity requirements for Google ads in its AdSense for Search contracts in 2009.

In the coming days, Alphabet is also expected to fire off its response to another set of EU charges issued in April over the tech giant's conduct with its Android mobile operating service--allegations that threaten to undermine how Google makes money from mobile devices, which have rapidly become users' primary portal to the internet.

Write to Natalia Drozdiak at natalia.drozdiak@wsj.com and Sam Schechner at sam.schechner@wsj.com

(END) Dow Jones Newswires

November 03, 2016 11:14 ET (15:14 GMT)

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