Four members of the Lee family, which controls Samsung, are now the richest people in South Korea, marking the first time that the country's top four billionaires all hail from the same family. Shares of their crown jewel, Samsung Electronics, surged 40% over the past month, driven by soaring demand for its memory chips needed for AI.

South Korea's richest person, Jay Y. Lee, the executive chairman of Samsung Electronics, now boasts a net worth of $34 billion, according to Forbes’ Real-Time Billionaires list, up by $12.4 billion from late March when net worths for the list of the country’s 50 richest was finalized. His younger sisters Boo-jin ($12.4 billion) and Seo-hyun ($12 billion) and mother Hong Ra-hee ($11.2 billion) have become the country's second-, third- and fourth richest, respectively. Boo-jin is the president and chief executive of Hotel Shilla, one of Seoul's top lodging and conference centers; Seo-hyun is president of strategic planning at Samsung C&T, the Samsung group's de facto holding company; Hong was the director of the Samsung Museum of Art, known as Leeum, and the Ho-Am Art Museum before her resignation in 2017.

The Lees derive the bulk of their wealth from shares of Samsung Electronics, which have soared five-fold over the past year. The company is the largest maker of memory chips needed for AI by sales. Its high-bandwidth memory—or HBM—is used to power AI chips, such as those from Nvidia, AMD and Alphabet. Demand for Samsung Electronics' commodity memory chips has also been robust. For example, its NAND flash, which is used for long-term storage in solid-state drives, is deployed in data centers to store the enormous datasets required for AI.

Last week, Samsung Electronics' market capitalization hit $1 trillion, making it only the second Asian company, after Taiwan's chip making giant TSMC, to join the four-comma club. Last month, the company reported record quarterly revenue and profit, powered by its chip unit. Revenue rose 69% year over year in the first quarter to 133.9 trillion won, while operating profit jumped 756% to 57.2 trillion won.

In a recent note, Barclays analysts said they expect Samsung to triple HBM revenue this year. “The demand/supply imbalance shows no signs of improving any time soon and with memory content taking a material step up in 2027 datacentre architectures, the accelerating capacity being brought online is unlikely to close the gap materially this year or next in our view,” they added.

Jay Y.’s late father, Lee Kun-hee, died in 2020 at 78, leaving his family with one of the largest inheritance tax bills in the country's history. Kun-hee's father, Byung-chull, founded Samsung in 1938 as a trading company, which quickly transformed into a sprawling empire with interests in food, textiles and electronics, among other sectors.

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