Chips ends up mixed as Arm slips with Bernstein starting at underperform
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Semiconductor stocks started the week mixed on Monday as investment firm Bernstein initiated coverage on Arm Holdings (NASDAQ:ARM) with an underperform rating. 
Analyst Sara Russo noted that the share price of the British chip design firm is at a premium on the hope that it will soon see benefits from artificial intelligence, but that likely will not occur in the short-term.
"We believe two of the biggest risks to the Arm growth story for the next 2-3 years are competition from RISC-V and their distance from the China business, which was [roughly] 25% of revenues last year," Russo wrote in an investor note.
Arm (ARM) shares closed down more than 4.5%, after jumping more than 25% on Thursday, which resulted in the firm having a valuation around $68B.
Other semiconductor stocks were mixed on Monday, with Nvidia (NVDA), AMD (AMD) and Intel (INTC) seeing fractional gains and losses. 
The Competition and Markets Authority, the U.K.'s antitrust agency, laid out seven new principles to regulate artificial intelligence on Monday and said it would speak to Nvidia (NVDA), among several other companies, on the matter. Findings are slated to come early next year.
Intel (INTC) unveiled a new glass substrate material to be used for advanced packaging on Monday, which it said will allow for the "continued scaling" of transistors and push Moore's Law for data-centric applications, including artificial intelligence.
Micron (MU) shares ended modestly higher as Deutsche Bank upgraded the memory maker, citing "inflecting fundamentals."
"Our recent checks with the supply chain suggest that the price increases are sustainable and should accelerate in the next two quarters given the limited supply growth," analyst Sidney Ho wrote in an investor note.
Other chip stocks saw fractional moves, including Broadcom (AVGO), Analog Devices (ADI), Texas Instruments (TXN) and Qualcomm (QCOM).

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