The reversal comes on a day where the entire market saw a steep drop following a mediocre jobs report. The Dow closed down 2.2 percent and the Nasdaq Composite Index closed down 3.1 percent.
Apple had already been struggling to hang onto its spot as the world's most valuable public company. It was once again eclipsed by Microsoft on Friday after returning to the lead at the start of the week. Amazon has also challenged both companies for first place.
Apple has been slipping in share price amid speculation that its flagship product, the iPhone, is headed toward slower growth. This speculation was fueled by Apple's announcement during its fourth quarter 2018 earnings call that it would no longer report unit sales for the iPhone. Not long after, several key iPhone suppliers cut their revenue forecasts.
Alphabet has also been under a microscope recently. Google CEO Sundar Pichai is expected to testify about the company's policies at a House Judiciary Committee Hearing that was postponed to Tuesday. There, he will likely face questions about potential bias in Google's search results and the company's proposed plans to reenter China with a censored version of its platform. Google has also seen a recent uprising from employees who were discontent with the company's sexual misconduct policies and treatment of temporary and contract workers.