Data storage companies slip after Samsung's results

** Shares of US data storage companies decline premarket after Samsung Electronics' 005930.KS Q3 results

** Samsung disappointed investors with a lack of fresh shareholder-return plans and an outlook that lagged rival SK Hynix's even as its Q3 profit jumped nearly ninefold on robust AI-chip demand

** Seagate Technology STX.O falls 3%, Western Digital WDC.O down 2.8%

** Sandisk SNDK.O slides 2.9%

** The industry has drawn scrutiny in recent weeks on growing concerns over the sustainability of AI spending

** As of last close, STX and WDC shares more than doubled YTD, while SNDK up about fivefold