The stock market’s valuation is giving dot-com bubble vibes. Bank of America strategist Michael Hartnett pointed out that the S & P 500 is trading at 5.3 times its price-to-book value. His data shows that valuation is higher than that in March 2000 — when the internet bubble peaked and began to burst, eventually sending the benchmark into a bear market. FactSet data also puts the index’s valuation near levels not seen since the late 1990s dot-com bubble. Price-to-book measures the value of a company’s assets minus its liabilities. “It better be different this time,” Hartnett wrote in a Thursday note to clients. The sky-high valuation comes as investors continue to pile into artificial intelligence-related stocks such as Nvidia , while expectations around Federal Reserve rate cuts have skyrocketed thanks to inflation data released earlier this week. The S & P 500 eked out another record close on Thursday and is headed for its fourth weekly gain in five weeks. Hartnett gave several reasons why the market may not suffer the same fate it did a quarter century ago, when similar valuations were present. Among them are investor aversion to bonds, millennials and Gen-Z’ers gravitating more to stocks than real estate to build wealth and, of course, the AI boom. But the problem is that only a handful of megacap tech stocks are driving the bulk of the S & P 500’s latest run to all-time highs. Should any of them falter (think of Meta Platforms , Nvidia, Amazon or Microsoft ), it will drag down the S & P 500 — possibly sparking a similar move to the one at the turn of the century. If it’s “not different this time, bonds get some love, international stocks > S & P500 continues,” Hartnett said.