Cerebras Systems and Cisco Systems fell sharply Thursday even as both companies produced fresh signs that demand for AI infrastructure remains robust, highlighting a market shift toward judging AI beneficiaries on the pace of revenue acceleration, margin expansion and monetization. Cerebras was down 13% at the time of writing after earlier falling about 16% in premarket trading. It reported record core revenue of $209.9 million, up 103% year over year, with core cloud and services revenue up 287%, remaining performance obligations of $25.4 billion and higher full-year guidance. Yet its third-quarter core revenue outlook of $214 million to $216 million implied only about 2.4% sequential growth at the midpoint, while core gross margin is expected to dip to 38% to 40% before recovering in the fourth quarter. Cisco fell about 8% even after booking $4 billion of hyperscaler AI infrastructure orders in the fourth quarter, taking fiscal 2026 orders to $9.3 billion, projecting $7.5 billion of hyperscaler AI revenue in fiscal 2027 and reporting an 18% rise in revenue to $17.25 billion. Morgan Stanley analysts said "execution remains the key debate" for Cerebras, and Jake Behan, Direxion's head of capital markets, said Cisco's results largely confirmed expectations that were already priced in. Sentiment around the wider theme remained firm, with prediction-market platform Polymarket putting the odds of a severe AI-industry downturn by year-end at 14%, down from 27% in late July on roughly $2.9 million in trading volume.