NuScale led an SMR-and-fuel selloff on a UBS downgrade to Sell, reversing Thursday's post-vote rally, while specialty-alloy name ATI led.

ATI Inc. (ATI) led, up 4.4% to $191.63 — the specialty-alloy and reactor-materials supplier was, tellingly, the only real strength in an otherwise red nuclear tape, and the reversal of its own role is the story: ATI was the laggard just one session earlier. No fresh company disclosure drove Friday's bounce; it read as a return to the cyclical-materials edge of the basket that maps the alloys-and-forgings rung, while the reactor developers that had run on Thursday's policy catalyst gave it all back. GE Vernova (GEV) +1.7% to $940.33 and BWX Technologies (BWXT) +0.8% to $147.52 were the only other names to hold green, both on the established equipment-and-fuel tier.

NuScale (SMR) was the laggard, down 8.5% to $8.27, after UBS downgraded the stock to Sell from Neutral and cut its price target to $6 from $10, flagging long deployment timelines, weak customer visibility, and heavy expected cash burn; a plaintiffs' firm separately announced an investigation. The move sits directly on the developer chokepoint the vertical tracks — the small-modular-reactor names that still carry no revenue-generating projects — and it dragged the whole speculative rung with it. This was a clean reversal of Thursday's bounce on the House's passage of the Ratepayers Protection Act, not a new leg down: the policy read-through to behind-the-meter generation is intact, but the market repriced how far off real deployment remains.

The weakness spanned the fuel-to-build stack. Oklo (OKLO) fell 4.2% to $38.00 and NANO Nuclear (NNE) −7.3% to $15.73 on the developer tier; the enrichment-and-fuel chokepoint gave back with Centrus (LEU) −3.1% to $145.23, Uranium Energy (UEC) −3.1% to $9.81, enCore Energy (EU) −7.2% to $0.90, and Lightbridge (LTBR) −4.4% to $6.52; X-Energy (XE) −3.4% to $15.77 unwound Thursday's leader print. Japan Steel Works, one of the few suppliers of large reactor-pressure-vessel forgings, fell in its Tokyo session — the heavy-forging bottleneck moving with the developer sentiment rather than any program news. The pattern was the mirror image of Thursday: the names that gate whether SMRs get fueled and built led the decline, while the diversified materials-and-equipment suppliers held.

The catalysts ahead are regulatory and contractual. The NRC's final Environmental Impact Statement for GLE's Paducah laser-enrichment facility is due around quarter-end — a step toward the domestic HALEU supply the whole SMR fleet needs — alongside a USGS critical-minerals reassessment cycle touching zirconium supply. X-Energy's Xe-100 construction permit hits an NRC 18-month review milestone December 16, and definitive Westinghouse/US-government agreements replacing the binding term sheet are expected by year-end. BWXT reports Q3 on November 2 and NANO Nuclear gives a fiscal year-end update November 15.