Billionaire families bet on semiconductor and energy stocks in first quarter during Iran war

Billionaire family offices increased exposure to semiconductor and energy stocks in Q1 2026, according to CNBC’s analysis of SEC filings. Appaloosa (David Tepper) raised stakes in Micron (+11% to $562.5M) and Taiwan Semiconductor (+18% to $448.6M) and added a new $179M Sandisk position. Soros Fund Management boosted its Nvidia stake by 61% to $187M. Duquesne (Stanley Druckenmiller) opened positions in Sandisk and Broadcom and locked in gains by exiting Entegris and ON Semiconductor. Semiconductor names have rallied sharply—Sandisk and Micron rose roughly 50% and 60% over the past 30 days, while Broadcom, TSM and Nvidia are up about 35%, 19% and 28% since the end of March—making the family office bets timely. Energy positions were mixed: some firms increased exposure (e.g., Vistra) while others exited amid soaring oil prices; certain offices trimmed airline holdings due to fuel concerns.