Shares of ChangXin Memory Technologies (CXMT), China’s leading DRAM maker, jumped 12 per cent on Monday to close at a record 61.80 yuan (US$9.16), lifting its market capitalisation to 4.13 trillion yuan and extending its lead as China’s most valuable listed company. The Hefei-based chipmaker first overtook Hong Kong-listed Tencent Holdings on Thursday as China’s most valuable listed company, when CXMT’s market value reached about 3.54 trillion yuan. It had already become the most valuable company on mainland exchanges on its July 27 trading debut, when the stock surged 466 per cent. Monday’s close left CXMT more than seven times above its 8.66 yuan initial public offering price. The latest jump appeared largely sector-driven. SanDisk shares surged nearly 30 per cent on Thursday and Friday after its investor day reinforced expectations that artificial intelligence (AI) demand could keep memory supplies tight, while Micron Technology also gained 6.7 per cent last Friday. SanDisk had reported strong quarterly results earlier this month. At its investor day last week, the NAND maker also forecast solid long-term growth and margins, further boosting confidence in the memory upcycle. Nomura said the investor day provided greater long-term visibility into the NAND market, pointing to SanDisk’s forecast that solid-state drive (SSD) shipments for AI data centres could reach 1,200 exabytes in 2030. An exabyte equals 1 million terabytes. Wall Street research firm Bernstein said the presentation made it more bullish on SanDisk, arguing that AI was shifting from a “compute-centric” to a more “memory-centric” architecture as larger models and longer context windows raise memory requirements. It also noted that SanDisk’s planned high-bandwidth flash technology could consume substantially more wafer capacity than conventional NAND, potentially keeping supplies tight for longer. UBS initiated coverage of CXMT with a “Buy” rating and a 70 yuan price target earlier this month. The bank expected global DRAM undersupply to persist until at least the second quarter of 2028 and was forecasting CXMT’s capacity to rise to 466,000 wafers per month by the end of 2028 from 240,000 at the end of 2025, lifting its share of global DRAM bit supply to around 10 per cent from 7 per cent. It expected that data-centre applications would account for 54 per cent of CXMT’s revenue by 2028. CXMT has been one of the biggest beneficiaries of the memory upcycle. Its first-quarter revenue jumped 719 per cent, year on year, to 50.8 billion yuan, while net profit reached 24.8 billion yuan, reversing a loss from a year earlier. The company is the world’s fourth-largest DRAM producer, behind Samsung Electronics, SK Hynix and Micron. In a separate sign of China’s accelerating AI boom, domestic AI developer SenseTime said on Sunday that the company was expected to have turned a profit in the first half of the year. If confirmed in the official earnings results, that would mark its first consolidated profit since its listing in 2021. SenseTime shares surged 8.9 per cent to HK$1.53 in Hong Kong on Monday.