Alphabet (GOOGL) stock is up today: Alphabet Inc. (GOOGL) shares jumped over 1% on Monday, January 12, 2026, as the tech giant officially joined the elite $4 trillion market cap club. This historic rally follows a landmark multi-year AI partnership with Apple. Google’s Gemini will now power the next generation of Siri. This deal cements Alphabet's lead in the global AI race, pushing the company’s valuation past Apple for the first time since 2019.