Alphabet shares tumbled Thursday following news that the Department of Justice is pushing for a proposed breakup of the tech giant. This could include a forced sale of its Chrome web browser and potentially unwinding its partnership with artificial intelligence startup Anthropic to end its illegal search monopoly. 

The DoJ wrote in a Wednseday filing, "To remedy these harms, the Proposed Final Judgment requires Google to divest Chrome, which will permanently stop Google's control of this critical search access point and allow rival search engines the ability to access the browser that for many users is a gateway to the internet." 

Sources told Bloomberg that the provision would likely apply to Google's Anthropic investment as well.