The biggest antitrust trial in decades got underway on Tuesday, Sept. 12 – The U.S. Justice Department v. Google. The U.S. claims Google violated antitrust laws by paying billions of dollars to Apple and other partners in order to become the default search engine on its devices and web browsers.

The Justice Department and 10 states sued Google three years ago. Over the next 10 weeks, federal prosecutors will try to prove Google is illegally maintaining a monopoly in online searching. Google commands about 90% of the internet search marketplace.

“This case is about the future of the internet,” said Justice Department lawyer Kenneth Dintzer during opening remarks in a federal court in Washington, D.C.

The lawsuit claims Google’s agreements with partners like Apple, Mozilla, Verizon and Samsung are illegal because they prevent competitors from getting enough search queries to improve their own products.

“Google pays more than $10 billion per year for these privileged positions,’’ Dintzer said.

Google argues while it faces a wide range of competition, from Microsoft’s Bing to websites like Amazon and Yelp, the company says people prefer its search engine because it’s a superior product.

Top executives at Google, its parent company Alphabet and potentially Apple are expected to testify. The Justice Department sued Microsoft in 1998 for similar reasons. A federal judge ruled Microsoft violated antitrust laws and ruled the company to be split into two. Microsoft appealed and that part of the ruling was overturned.