OpenAI’s Latest Funding Deal Returns Focus to AI Economy, Lifting U.S. Stocks

1. OpenAI's $500 billion valuation lifted U.S. stocks to record highs. 2. Nasdaq and S&P 500 closed at all-time highs, driven by tech and AI. 3. Semiconductor stocks rose significantly; sector insulated from government shutdown. 4. Investors await corporate earnings as key indicators during data void. 5. Strategists caution about the tech rally outpacing fundamentals.