Bank of America strategist warns about super large IPOs like SpaceX, saying market concentration will surpass the level during the bubble period.

Michael Hartnett, a strategist at Bank of America, stated that the mega IPOs planned by SpaceX and OpenAI could potentially push the weight of tech stocks in the stock market benchmark index beyond the concentration levels seen during market bubble periods. Elon Musk's SpaceX has set up the world's largest initial public offering plan, while OpenAI, the developer of ChatGPT, is attempting to go public ahead of its competitor Anthropic. These massive stock offerings will fuel optimism surrounding tech and artificial intelligence stocks, a sentiment that has already driven one of the narrowest and longest-lasting bull markets in decades. Hartnett said in a report, "Strong price action, retail frenzy, declining volatility... the bubble is too strong." He added, "Adding mega IPOs to the AI giants could easily push market concentration beyond the roaring 20s, the 'Nifty Fifty' of the 70s, Japan in the 80s, and the tech media telecom bubble of the 90s."