Alphabet has reached a $4 trillion valuation, joining Nvidia, Microsoft, and Apple in this elite group. This milestone follows a 1% rise in share price fueled by Apple’s selection of Google’s Gemini technology for its AI and Siri updates. Alphabet's stock surged 65% in 2025, adding roughly $1.5 trillion to its market value. Analysts like Deepak Mathivanan believe Google possesses a competitive advantage in AI, amidst rising demand in the sector.