The move makes Google's home state the first one with a Democratic administration to seek to join the DOJ and 11 Republican attorneys general in the lawsuit. California did not join the initial group of 50 states and territories that launched an investigation into the search giant last year, but Politico later reported it had been pursuing its own probe.
A Google spokesperson referred CNBC to the company's previous response to the DOJ lawsuit which called the complaint "deeply flawed."
State Attorney General Xavier Becerra, who recently became President-elect Joe Biden's pick to lead the Department of Health and Human Services, said in the filing that California would not seek any changes to the original complaint announced in October.
"By using exclusionary agreements to dominate the market, Google has stifled competition and rigged the advertising market," Becerra said in a press release. "This lawsuit paves the way for search engine innovation with greater regard for privacy and data protection."
Several other states have said they are continuing to investigate Google. If they file their own complaints, they may seek to join them with the existing lawsuit, potentially expanding the allegations against the company.
The DOJ lawsuit claims Google has unlawfully maintained a monopoly in online general search by depriving rivals of key distribution channels.