Recent scientific breakthroughs have sparked a massive boom in artificial intelligence (AI) innovation. Data from the United States Patent and Trademark Office (USPTO) show that the number of patent filings for AI technology has increased at least tenfold since 2015. How is this fast technological progress affecting economic growth? In this article, we answer this question by studying 30 years of innovation in AI, linking the response of the stock market, firms, and economic sectors to the deployment of relevant AI technologies. We find that AI patents are associated with significant stock market responses. The valuation of firms after an AI patent increases, on average, by $71 million—larger than the response to any other type of patenting. Firms that develop an AI patent grow significantly faster than those developing other types of innovation, indicating the value of AI innovations to individual firms. However, despite these individual success stories, we find that AI’s impact is not yet visible at the aggregate level, suggesting that while the technology is powerful, its adoption is currently too limited to drive major economy-wide productivity gains.