Cerebras Systems is trading 13.71% down at $79.26 after a November 5 notice reported Culper Research’s short position and allegation that its wafer-scale AI processors could fail within approximately 1.5 to 2.5 years; these are not established findings. - Semiconductor and data-center stocks faced pressure from concerns that tighter AI infrastructure regulation could slow construction, alongside weak smartphone-chip demand affecting the sector. - The price context shows the sharp decline extending a recent volatile stretch.