
Arm's Total Market Cap Surpasses $300 Billion for the First Time; Masayoshi Son Reaps $220 Billion Profit, Creating an Investment Legend
Driven by global demand for AI computing power, Arm's total market capitalization has exceeded $300 billion for the first time. During trading on May 21, the stock price surged 11% to $284.49, reaching a market cap of $302.7 billion, following a gain of over 15% in the previous session. Major shareholder SoftBank holds approximately 87% of the shares, with paper profits exceeding $220 billion and a return rate of 550%
Driven by a surge in global demand for AI computing power, Arm's total market capitalization has surpassed the $300 billion mark for the first time.
At the start of U.S. trading on May 21, Arm's stock price surged 11%, hitting a record high of $284.49, with its market capitalization exceeding $302.7 billion. In the previous trading session, the stock had already jumped 15.05%, closing at $256.73 after reaching an intraday high of $259.44.
This milestone marks the most lucrative investment legend for major shareholder SoftBank and Masayoshi Son. It is estimated that SoftBank holds approximately 87% of Arm's shares at a cost of about $40 billion, currently recording paper profits of over $220 billion, representing a 550% return.
Meanwhile, SoftBank's shares in Japan surged nearly 20% today. On the news front, OpenAI, in which SoftBank holds more than a 10% stake, reportedly plans to list in the United States. Additionally, SB Energy, a digital infrastructure company invested in by SoftBank, stated it would secretly file a registration statement.

Bernstein Gives Arm an "Outperform" Rating
The catalyst for Arm's recent rise comes from Bernstein's latest report. The firm assigned an "Outperform" rating to Arm with a target price of $300, implying approximately 16.8% upside potential from the current stock price. Bernstein believes that Arm is not only a beneficiary of chip design in the AI wave but will also structurally dominate the next era of computing.
Bernstein's core judgment revolves around the rise of agentic AI. As the industry shifts from conversational chatbots to AI agents capable of autonomously executing multi-step tasks, central processing units (CPUs) are returning to the center of the technological stage. Leveraging its energy efficiency advantages, Arm is poised to quadruple its CPU market share within the next four years, corresponding to a $137 billion addressable market. Bernstein expects Arm's profits to grow fivefold by 2030.
This optimistic expectation is built on solid financial data. In the most recent fiscal quarter, Arm's net profit increased by 49% year-over-year to $313 million, while revenue grew by 20% to $1.49 billion, demonstrating the continued expansion of demand for its chip architecture across sectors from mobile to cloud computing.
