The advanced-reactor platform names sold off together as Oklo's dilution disclosure soured the SMR cohort, while firmer uranium spot pulled the fuel-supply side the other way.

The session split cleanly along the fuel cycle: the reactor-platform layer sold off, and the fuel-supply layer led. enCore Energy topped the basket, up +4.8% to $1.31, with no company-specific headline — the move tracked firmer uranium, with spot around $86.80/lb on Monday, and enCore's high spot-price leverage as a U.S. in-situ-recovery producer made it the cleanest way to play it. At the uranium-supply chokepoint the read was rotation: on a day the market punished pre-revenue reactor stories, it rewarded the names that actually dig and process the fuel those reactors will someday need.

The laggard was the sharpest expression of the opposite trade. X-Energy fell −8.9% to $20.64 at the fuel-fabrication choke — the session's biggest decliner and the highest-beta name in the SMR cohort. There was no fresh X-Energy news; it fell on two structural drags at once. The whole advanced-reactor group was de-rating after Oklo's Friday print, and X-Energy carries a well-flagged IPO lockup overhang — it listed on Nasdaq in April at $23, and the 180-day lockup expires in early September, pulling the stock back toward its offer price. Its own Q2 report lands August 13, which will put actual numbers under a name that has traded mostly on narrative.

The through-line was Oklo. Oklo reported Q2 on Friday and popped on the call, then reversed −8.1% to $44.49 on Monday as the market digested what the report actually contained: roughly $1.9B raised through at-the-market equity in 2026 — real dilution — and a raised guide for operating cash burn ($120–150M) and capex ($400–500M) against a still pre-revenue business. NuScale went with it, −6.5% to $9.18, digesting a revenue air-pocket after its own Q2 as the RoPower engineering phase rolled off, and Lightbridge −6.0% at fuel fabrication. Fluor fell −8.3% to $52.25, but that was a giveback of Friday's ~17% earnings spike, not an SMR-exposure story — Fluor completed its NuScale monetization in April. Against the platform rout, the fuel-and-forgings side held: Silex's ADR +2.6% at enrichment-HALEU and Huntington Ingalls +2.0% at the heavy-forgings choke.

The calendar keeps the platform layer in the spotlight. X-Energy reports Q2 on August 13 — the laggard's chance to put fundamentals under the lockup overhang. Solstice Advanced Materials prints Q2 on September 2 at the conversion-and-deconversion choke, and the World Nuclear Symposium convenes in London September 9–11, the fuel cycle's main annual gathering. Further out, the NRC's final environmental statement for GLE's Paducah laser-enrichment facility is targeted for September 30 — a genuine catalyst for the domestic enrichment bottleneck, as opposed to the funding-and-dilution questions now hanging over the reactor developers.