Alphabet (GOOG.O) shares plunged more than 6%, amid reports that Apple (AAPL.O) is considering adding artificial intelligence search functionality to its browser, potentially challenging Google's dominant position in the search field. Meanwhile, Apple's Senior Vice President of Services, Eddy Cue, revealed that the company's browser search volume saw a decline for the first time in April. Cue also mentioned that Apple is actively exploring adding artificial intelligence search functionality to its browser, sparking concerns about Alphabet's future search revenue share. These comments suggest that Apple may be seeking to reduce its dependence on Google's search engine, which could impact Alphabet's advertising revenue.