Andreas Halvorsen's Viking Global Investors significantly reduced its stake in specialty materials company ATI Inc. by 65.38%, an estimated trade valued at $429.47 million. The firm sold over 2.18 million shares, leaving its current holding at 1.15 million shares, which were valued at $227.43 million at the end of the second quarter.
This portfolio adjustment was disclosed in a quarterly 13F filing, which reflects positions held as of June 30, 2026, and does not represent a real-time trade. The reduction came ahead of ATI's strong second-quarter earnings report on August 6, where the company beat analyst expectations and raised its full-year outlook, supported by high demand from the aerospace and defense sectors.