Ark Invest bought another 78,756 shares of Cerebras Systems, extending one of Cathie Wood's most aggressive position-building campaigns of 2026 as the firm continues rotating capital into AI hardware. Ark has accumulated CBRS steadily since the company's May 13, 2026 IPO at $185 per share, after which the stock closed its first trading day at $311.07, up about 68%. Purchases cited in the latest account include 124,905 shares in mid-to-late May, 111,989 shares on June 25 and 106,941 shares on August 13 at $231.01 per share, a trade valued at about $28 million. Ark has funded part of the buildout by trimming holdings including Palantir and Shopify. The bet centers on Cerebras' Wafer Scale Engine, which uses an entire silicon wafer as a single processor for training large AI models, and on business momentum that included second-quarter core revenue of $209.9 million, up 103% from a year earlier, alongside higher full-year guidance. The continued buying also shows Ark's willingness to add through volatility as Cerebras trades below its first-day close and works through the margin pressures common to scaling novel hardware.