Arm's chip designs were inside more than 99 percent of the world's smartphones, yet Arm made no chips at all. It licensed blueprints to the companies that did, and collected a royalty on each one sold. More than 250 billion Arm-based chips had shipped by the time it filed. In September 2023 the AI boom had made chips the hottest corner of the market. SoftBank, which had bought Arm seven years earlier, brought it back to the public markets.

Acorn, Apple and VLSI

Arm began in Cambridge, England, in November 1990 as a joint venture of Acorn Computers, Apple and VLSI Technology. Its job was to design processors that used little power. The bet was to sell designs, not silicon, and let partners build the chips. That model put Arm in phones, cars, sensors and servers. SoftBank bought Arm in 2016 for about £24 billion and took it private.

SoftBank Sells a Slice

In 2020 Nvidia agreed to buy Arm for about $40 billion. Regulators in Europe, Britain and the United States pushed back, and the deal fell apart in February 2022. SoftBank chose an IPO instead. It sold 95.5 million American depositary shares at $51 each, and Arm listed on Nasdaq on September 14, 2023. The sale raised $4.87 billion at a $54.5 billion valuation, and SoftBank kept about 90 percent. Arm still trades on Nasdaq as ARM.

Cover: Study of a Nude Seen from the Back, and Two Studies of an Arm, Perino del Vaga. Art Institute of Chicago, public domain. Chosen for studies of an arm (the name, and the reach).