CXMT Tops Shanghai Composite at 4.67% Weight, STAR Market at 15.74%
ChangXin Memory Technologies joined the Shanghai Composite on Oct. 28 as its largest stock, three months after listing; Huayuan Securities sees 25.075 billion yuan of index buying.
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CXMT's index debut in numbers: a 15.74% weight in the STAR Market Composite and admission after the three-month rule.
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ChangXin Memory Technologies (CXMT), China's largest DRAM maker, was added to the Shanghai Composite Index on Oct. 28 with a 4.67% weight, the largest of any constituent, three months after its July 27 listing, according to China Securities Index Co. data cited by Seoul Economic Daily and Global Times.
CXMT's 4.67% weight is the largest in the Shanghai Composite, ahead of Agricultural Bank of China and ICBC, according to Global Times and Seoul Economic Daily.
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It also joined the STAR Market Composite, the Shanghai board for science and technology companies, at 15.74%. That is the top weight there, ahead of Cambricon at 5.05%. Within the Shanghai Composite, CXMT is ahead of Agricultural Bank of China at 3.83% and Industrial and Commercial Bank of China (ICBC) at 3.77%, the Seoul Economic Daily report said.
How the Index Inclusion Rule Works
Newly listed companies that rank among the top 10 by average total market capitalization since their IPOs are admitted to both indices after three months, Global Times reported, citing the index methodology. CXMT met that threshold on Tuesday, Oct. 27. Weight factors are adjusted on the trading day after the second Friday of each month, or when a new constituent's weight exceeds 15%.
Seoul Economic Daily said CXMT shares closed at 44.36 yuan on Oct. 28, up 3.16%, for a market value of 3.01 trillion yuan. The stock had surged 400% on its first day of trading, and MSCI added it to the MSCI China All Shares Index in August under its treatment for large IPOs.
What It Means for Memory Supply
The weight turns a China DRAM supplier into a position that index-tracking funds must hold. Huayuan Securities estimated that inclusion in five indices could create about 25.075 billion yuan ($3.76 billion) of buying demand for CXMT shares. The firm expects the STAR 50, STAR ChiNext 50 and STAR Chip indices to add the stock at the December rebalancing. The CSI 300 and CSI A500 require a full year of listing, so those come later.
For memory buyers, the point is scale. At a 3.01 trillion yuan market value, CXMT is the heaviest stock on the Shanghai market while it works on the DRAM and high-bandwidth memory (HBM) lines Voltgrid has covered, including its reported plan for HBM3E output at 20% to 30% yields. Whether the capital translates into more output is not addressed in these reports.
What Is Not Confirmed Yet
The Huayuan figure is a broker estimate, not an announced flow, and index buying depends on when funds rebalance. The reports do not say how much of CXMT's float is tradable, and none of them gives a CXMT statement on the inclusion.
