COHU is trading 4.05% down in pre-market at $63.30, versus the September 29 close of $65.97; the reason for the drop remains unclear. - Supplied market indicators were mixed, with no broad-market decline greater than 0.5%, and do not establish a market-wide explanation. - On September 29, Cohu announced that management would participate in an investor summit on October 13; no connection to the decline was stated, and no clear company-specific catalyst for the September 30 move was identified.