Sundar Pichai, the CEO of Alphabet and its subsidiary Google, is set to testify on Monday in the landmark antitrust trial US v. Google. Pichai will be one of the first primary witnesses that Google calls for its defense.

The US Justice Department and a coalition of state attorneys general are leading the trial after a three-year-long case. The government alleges that Google, with about 90% of the search market, abused its dominance and paid billions of dollars annually to smartphone makers, mobile service providers, and others to be the default in search on their devices.

Why does it matter?

The trial is expected to last for ten weeks, and Pichai's CEO testimony is a crucial part of Google's defense. He will insist that Google's search success is the result of its investment and innovation in search and search advertising and not deals with big companies such as Apple or AT&T. The outcome of this trial could have wide-ranging implications for Google and, globally, represent a significant challenge to the operations of the tech industry. After the US, the EU, and other major economies, Japan recently opened an antitrust investigation into Google search practices.