Shares of Sandisk soared 22% to $334.75 without an obvious catalyst on Tuesday as investors continued to pour money into the flash memory company. Sandisk began trading at $36 a share last February after spinning off from Western Digital The stock has since joined the and surged more than 800% since the spinoff, with artificial intelligence boosting demand for solid state drives and other data-storage hardware. Tuesday was Sandisk’s largest single-day jump since Feb. 18, 2025, according to Dow Jones Market Data.