The AI-capex selloff hammered the quantum hardware and photonics complex — Arqit down 18.3% and Coherent off 9.6% — while IBM's value bid left it the rare gainer, up 2.8%.

IBM (IBM) was the rare green in the quantum basket, up 2.8% to $226.61. The session was risk-off — a Financial Times report that OpenAI's annualized revenue was running near $50bn, below the roughly $70bn investors had penciled in, cracked the AI-capex trade and knocked a gauge of chipmakers down about 3.4%, while yields and oil rose. IBM is the quantum name least exposed to that unwind: a cash-generative value stock whose quantum program — two modular cryogenic systems joined below 15 millikelvin in August, and a $10bn roadmap toward fault-tolerant machines by 2029 — is a long-dated option, not a capex-funded buildout being repriced today. GlobalFoundries (GFS) also rose, up 2.7% to $49.36, as a mature-node foundry with less leverage to the AI-accelerator cycle.

The laggard was Arqit Quantum (ARQQ), down 18.3% to $18.43. Arqit is a speculative quantum-encryption microcap, and no company-specific news accompanied the move — it reads as high-beta deleveraging as the broad AI and quantum trade came off and rates rose. The structural point is that the pre-revenue quantum names carry the most beta to risk sentiment and sit furthest from any funded demand, so they lead both the rallies and the retreats.

The photonics and control-electronics chokepoint took the brunt of the selling. Coherent (COHR) fell 9.6% to $302.35 — the lasers-and-optical rung that gates both qubit control and AI interconnect, and the highest-beta expression of that bottleneck. Quantinuum (QNT) −6.1% to $41.52, MKS Instruments (MKSI) −4.7% to $260.38 on the vacuum/photonics subsystem rung, and Intel (INTC) −5.3% to $107.08 followed. The pure-play qubit developers sold in sympathy: IonQ (IONQ) −4.6% to $39.45, D-Wave (QBTS) −4.1% to $14.60, Rigetti (RGTI) −3.1% to $14.14, and Quantum Computing (QUBT) −2.2% to $7.45. NVIDIA (NVDA), the classical-coprocessing rung that pairs with quantum systems, eased 2.9% to $230.48.

The next hard catalysts sit on the funding rung. The DARPA Quantum Benchmarking Initiative's Stage B-to-Stage C downselect window opens in November (date estimated) — the program that separates funded roadmaps from unfunded ones, and the cleanest near-term discriminator for the hardware names that just sold. Coherent reports fiscal results in early November, the next read on the photonics chokepoint's order book. Q2B26 Chicago (Dec 8–10) is the next major industry gathering, where commercial-traction claims get tested against the venture-funded qubit roadmaps.