Stocks: Semtech, Seagate, MACOM Shares Plunge Amid AI Chip Export Uncertainty

[Para 1: The Lead] U.S.-listed stocks of MACOM Technologies (MCOM), Seagate Technology (STX), and Semtech (SMTC) experienced significant declines on February 4, 2026, amid heightened uncertainty over delayed export licenses for advanced AI chips to China. The market reacted swiftly to the news, reflecting investors' concerns over potential disruptions in the semiconductor supply chain. [Para 2-3: Supporting details & Context] The U.S. government extended its review of export license applications for AI hardware, including Nvidia's H200 chips, citing national security concerns. This extension created market volatility, with some Chinese customers postponing orders until clearer guidance was provided. The impact was felt across major semiconductor exporters, including MACOM, Seagate, and Semtech, whose shares fell due to reduced sales expectations. The situation underscores ongoing geopolitical tensions affecting the semiconductor industry's global supply chain dynamics. Despite the downturn, Semtech, trading at $81.81 per share, is close to its 52-week high, indicating that while the market is reacting, it may not fundamentally alter the company's long-term outlook.