The stock market may have gotten ahead of itself with the excitement around the initial public offering of Arm Holdings , according to Bernstein. Analyst Sara Russo initiated coverage of the British chipmaker with an underperform rating, saying in a notes to clients that there should be more skepticism about Arm's exposure to artificial intelligence and its growth trajectory. "While expectations that Arm will be a beneficiary from AI growth may be adding a premium to the share price, we believe it is too soon to declare them an AI winner. In addition, we remain more conservative on their ability to deliver increased royalty rates at the pace management is guiding," the Bernstein note said. Arm debuted on Thursday after the company priced its IPO at $51 per share. The stock rose more than 20% on its first day of trading before giving back some of those gains on Friday . ARM 5D mountain Shares of Arm are still up from their IPO price of $51 per share. Bernstein has a price target of $46 per share for Arm, which is about 24% below where the stock closed on Friday. The disappointment for investors could come soon, as Bernstein projects that Arm's revenue will be below management guidance for the current fiscal year, which ends in March. "Mobile and consumer end markets make up close to 60% of revenues and both continue to be challenging, given cyclical headwinds. With the mobile end market maturing, we think expectations for top line growth are too optimistic," the note said. — CNBC's Michael Bloom contributed reporting.