Micron stock was slipping on Thursday as the recent rebound in the shares from a multi-week slump seemed to slow. Investors may want to catch a breath and look to a fast-growing rival in the memory chip market.

Micron shares were down 0.3% in premarket trading after a near 5% rally on Wednesday. While the stock remains up some 190% so far this year, it has slipped by almost a quarter since late June amid concerns including about the sustainability of chip pricing.

While demand for hardware used in artificial intelligence, such as memory chips made by Micron and peers such as SK Hynix, remains resilient, a competitive threat may be looming, according to new research.

Micron fell behind in the second quarter among suppliers of NAND memory chips -- storage used in applications from smartphones to AI alike, according to a report on Wednesday from Counterpoint Research. NAND is a critical sector for Micron, making up around a quarter of the company's revenue.

"AI has become the defining variable for NAND demand. As the AI paradigm shifts from training to inference, demand has surged," Counterpoint Research said. " Samsung maintained its lead with a 25% shipment share, followed by SK Hynix at 22%. YMTC climbed to third place with 14%, narrowly edging out Kioxia, with Micron trailing."

YMTC, Yangtze Memory Technologies Co., will be a name to watch, and could be a new Chinese memory threat for Micron.

The company may be a bit tricky for international investors to access -- and has been on the Commerce Department's Entity List, which targets foreign companies suspected of being against U.S. interests, since 2022. YMTC is preparing to go public in mainland China, though it has yet to disclose the date of an initial public offering.

Micron still edged out YMTC in one substantial metric, according to Counterpoint Research -- and that's revenue.

"Shipment volume, however, does not translate directly into revenue. YMTC ranked third in shipments this quarter but closed fifth in terms of revenue, behind Micron and Kioxia, because its product mix is still concentrated in consumer applications with a low share of high-priced data-center eSSDs," researchers said, referring to enterprise solid-state drives.

"The Chinese vendor plans to shift its mix further towards eSSDs in the second half of the year to cement its third-place position globally, supported by growing avenues for capital support."