Opening statements before District Judge Leonie Brinkema of the US District Court for the Eastern District of Virginia start later today. The BBC notes that the Justice Department plans to argue that Google's parent company, Alphabet, illegally operates a monopoly in the online advertising market. However, Alphabet denies the allegations, claiming that its success is due to the "effectiveness" of its services.

The Justice Department claims Google established its monopoly through the anti-competitive acquisitions of smaller ad-tech rivals and even bullying website publishers into using its ad products. Google is also said to have unethically controlled key businesses in each part of the advertising supply chain, thereby driving up ad rates for advertisers while reducing the payouts to website owners.

Pointing out Google's systematic abuse of the online ad business, the DoJ will ask the court to break up the company's ad-tech monopoly. The agency believes a breakup would create new opportunities for Google's smaller competitors and incentivize new players to enter the market. It will also be better for both advertisers and publishers.