Arm Holdings is trading 5.01% up at $307.00 in pre-market on October 2, 2026, as semiconductor shares and the broader market are higher; available reporting does not confirm the cause. - Semiconductor shares broadly strengthened as investors reacted to onsemi’s revised $5.7 billion all-cash Synaptics deal; no clear Arm-specific announcement surfaced. - Recent closes were volatile, including an 8.70% decline on September 28 and a 0.93% gain on October 1.