02:01 PM EDT, 03/31/2025 (MT Newswires) -- Tech stocks were in the red Monday afternoon, with the Technology Select Sector SPDR Fund (XLK) falling 1.4% and the SPDR S&P Semiconductor ETF (XSD) dropping 2.5%.

The Philadelphia Semiconductor index fell 2.1%.

In corporate news, GlobalFoundries ( GFS ) and United Microelectronics ( UMC ) are exploring a possible merger, Nikkei Asia reported. GlobalFoundries ( GFS ) shares were down 1.4%, while United Microelectronics ( UMC ) jumped past 9%.

Arm (ARM) expects its share of the worldwide market for data center CPUs to surge to 50% by the end of 2025, up from about 15% in 2024, Reuters reported, citing a senior executive. Arm shares were down more than 3%.

Apple ( AAPL ) and Elon Musk's SpaceX are clashing over the rights to use satellite technology to eliminate mobile phone network dead spots, The Wall Street Journal reported Sunday. Apple ( AAPL ) shares were rising 0.8%.