** Shares of chip designer Cerebras Systems CBRS.O fall 10.9% to $201.93 in premarket trading after its debut report as a public co included full-year profit margin forecast that lags rivals

** Co forecast FY26 adjusted gross margins of 38%-41%, down from 47% in Q1 and below rivals including Nvidia NVDA.O and Advanced Micro Devices AMD.O

** Weak forecast overshadows a strong Q2 sales outlook; co expects adjusted sales of $194 mln vs estimates of $174.34 mln, per LSEG data

** "While the need to build out cloud capacity has some risks, we see evidence in these numbers that the company has been conservative in projecting the ramp," Morgan Stanley says

** Cerebras, which raised $5.55 billion in its May IPO, focuses on inference, the process by which AI systems respond to user queries

** Ten of 11 analysts rate stock "buy" or "strong buy", one rates it "hold", per LSEG data