The AI-and-chip selloff hit robotics across both its silicon and its precision-mechanics rungs, with motion-control name Allient down double digits and nothing in the basket green except a barely-positive Enovix.

The leader was Enovix (ENVX), up 0.4% to $2.55 on the actuator-energy chokepoint — the high-density cells that power untethered humanoid and mobile platforms. The distinction is almost technical: on Thursday's broad risk-off tape, Enovix was the only name in the robotics basket to finish green at all. The session was a sharp AI-and-semiconductor selloff — the Nasdaq Composite fell 2.60% to 26,008.86 and the Philadelphia Semiconductor Index dropped 6.7% — triggered by revived doubts about the AI buildout and a Lam Research warning that chip supply could stay constrained through 2027. Everything else in the vertical, from silicon to steel, finished lower.

The laggard was Allient (ALNT), down 11.6% to $86.18 on the motion-control chokepoint — the precision motors, drives and controllers that are the physical bottleneck of any articulated robot. There was no confirmed company catalyst; this was a high-beta industrial-automation name swept down in the sector rout. It led a broad decline across the actuation rung: Teradyne (TER) −10.6% to $308.75 on test-and-robotics, Moog (MOG.A) −7.0% to $341.71, Regal Rexnord (RRX) −6.3% to $148.71, Timken (TKR) −5.7% to $108.40 and RBC Bearings (RBC) −5.2% to $478.03. The Japanese precision-reducer and bearing names — the harmonic drives and RV reducers that no Western supplier yet replaces at scale — fell in their own sessions alongside them.

The compute-and-perception rung, the robot's "brain," was hit as hard as its joints. Lattice (LSCC) −10.6% to $96.40 and Allegro MicroSystems (ALGM) −8.2% to $31.69 tracked the chip selloff, with STMicroelectronics (STM) −7.0% to $44.09, Synopsys (SNPS) −6.4% to $422.48 and NVIDIA (NVDA) −4.4% to $212.21. The embodied-AI and warehouse-automation names followed: Symbotic (SYM) −3.3% to $40.36, Cognex (CGNX) −5.9% to $54.60, Serve Robotics (SERV) −5.9% to $2.88 and Tesla (TSLA) −3.1% to $374.58. The rare-earth-magnet rung that gates every servo was red too: USA Rare Earth (USAR) −5.9% and MP Materials (MP) −2.4% to $38.56.

The near calendar is thick with hardware reads and one hard policy date. Hyundai Motor reports Q3 on October 27, Timken on October 30 and Schaeffler's nine-month results land November 3 — the industrial pulse behind the automation rung. China's one-year suspension of its October 2025 rare-earth export controls expires November 10, the single most important date for the magnet chokepoint, and the DFARS ban on Chinese-melted NdFeB and SmCo magnets in defense systems takes effect January 1. The Humanoids Summit in Silicon Valley on December 1 frames the demand narrative; until the November magnet date clears, the actuation supply chain, not the demos, is the constraint to watch.