Palantir Technologies Inc. is facing scrutiny over its high valuation, which some analysts believe could indicate a potential downside of 55% from its current share price. The company's valuation is being compared to other expensive stocks in the S&P 500, with particular emphasis on the need for consistent high growth in artificial intelligence (AI) and a 30% annual revenue growth rate to justify its valuation, which stands at approximately 50 times its revenue. Meanwhile, AppLovin has reached a valuation of $100 billion, although there are doubts about its sustainability in the long term.