Google has opened its defense against allegations that it holds an illegal monopoly on online advertising technology with witness testimony saying the industry is vastly more complex and competitive than portrayed by the federal government.

If the DoJ's lawsuit fails, the online ecosystem could worsen for users and third-party companies. Lawyers, nonprofit organizations, and privacy experts recently held a press hearing

Google faces a new lawsuit in Virginia alleging that the tech behemoth's dominance of online advertising amounts to a monopoly.

The US government has accused Google of manipulating the ad tech market, stifling competition and innovation; the company recently lost an antitrust case targeting its search business.

A senior Google executive sought to refute the US Justice Department’s antitrust case over its display advertising technology business, testifying that it faces “fierce competition” from the likes of Microsoft Corp.

As the government wraps up its case, it has built a picture of how Google has become dominant among companies that buy and sell ads online.

Google has monopolized the technology used to buy and sell online display ads by restricting or eliminating the choices of its customers — both website publishers and advertisers — the US Justice Department alleged at a federal antitrust trial.