Google’s parent company, Alphabet, has become the fourth company to reach a $3 trillion market capitalization, joining Nvidia, Microsoft, and Apple in this elite group. The milestone was achieved after a modest 4% increase in Alphabet’s stock price, fueled by growing investor confidence in the company’s AI strategy. The surge followed a favorable ruling from a federal judge earlier in September, who concluded that Google could retain its dominant position in internet search, citing generative AI as a future competitive force that could challenge its market power. In response, Google has accelerated its integration of artificial intelligence into its core products, most notably its search engine and the launch of its AI chatbot, Gemini. The release of Google Gemini has proven to be a major success, briefly making it the top free app on Apple’s App Store—outranking OpenAI’s ChatGPT. This strong consumer adoption has bolstered investor sentiment and contributed to Alphabet’s rising stock value. The broader tech sector has been riding a wave of AI-driven enthusiasm. Nvidia, the leading supplier of AI chips, became the first company to surpass a $4 trillion market cap earlier this year, driven by surging demand for its hardware. Microsoft followed suit, hitting the $4 trillion mark after reporting strong earnings from its Azure cloud platform, which has become a key infrastructure hub for AI development. Apple, while the first company to reach $3 trillion, has yet to cross the $4 trillion threshold and is considered the least directly involved in AI among the four. Oracle has also seen significant gains, with Chairman Larry Ellison becoming the world’s richest person after the company announced it expects to earn nearly half a trillion dollars in AI-related deals in the coming quarter. The stock soared over 42% on the news, highlighting how AI-driven revenue projections are reshaping investor expectations. Despite these impressive gains, concerns about an AI bubble are growing. OpenAI CEO Sam Altman acknowledged in a recent interview that investor excitement around AI may be excessive. A report from MIT reinforced these worries, finding that fewer than 10% of corporate AI pilot programs have delivered measurable revenue improvements. Meanwhile, U.S. Census Bureau data shows that AI adoption is not only limited to a few industries but is also beginning to decline in some sectors. Economists warn that if AI investment continues to outpace actual economic returns, the consequences could be severe. A Federal Reserve study published in July cautioned that such a mismatch could lead to “disastrous consequences,” drawing parallels to the railroad overinvestment of the 1800s and the subsequent economic downturn. Economist Torsten Slok has even argued that today’s AI bubble may be more dangerous than the dot-com bubble of 1999. While AI’s potential remains vast, the current market frenzy raises critical questions about sustainability, long-term value creation, and whether the current stock surge is grounded in real progress or speculative momentum.