Memory and storage stocks are extending a sharp rebound into Thursday afternoon trading, with SanDisk (NASDAQ:SNDK<\/a>) shares up 15% to $1,550 and SK Hynix (NASDAQ:SKHY<\/a>) shares climbing 9% to $168. Western Digital (NASDAQ:WDC<\/a>) shares are rising 7% to $487, leading a broad bid across the storage stack. <\/p>\n Meanwhile, Micron Technology (NASDAQ:MU<\/a>) stock is gaining 6% to $964, and Seagate Technology (NASDAQ:STX<\/a>) shares are advancing 5% to $922. For fund followers, the Roundhill Memory ETF (NASDAQ:DRAM<\/a>) is up 5% to $57 and change. <\/p>\n The Rally Started in Seoul <\/p>\n The move began well before SanDisk’s investor day. Korea’s Kospi surged 4% overnight on AI infrastructure optimism, with SK Hynix stock up 6% and Samsung Electronics stock up 5% in Seoul. <\/p>\n The Kospi now sits 23% above its July 30 low, and that Korea-led rotation into memory was already lifting the group before U.S. markets opened. SanDisk’s multi-year financial model unveiled at its investor day landed on top of an already-rising cohort rather than creating the move by itself. <\/p>\n The fundamentals of these memory\/storage large-caps support the bid. For example, SanDisk reported Q4 FY2026 revenue of $8.96 billion, up 371.6% year over year, while SK Hynix’s Q2 revenue jumped 256.8% on HBM demand. <\/p>\n Act now: the analyst who called NVIDIA in 2010 just named his top 10 AI stocks \u2014 and Western Digital didn’t make the cut. Grab the names FREE today<\/a>. <\/p>\n A Bounce Inside a Drawdown <\/p>\n Even with these immediate-term price bounces, it’s important to consider the bigger picture. Through Wednesday’s close, SanDisk stock was down 20% over the prior month. Also, Western Digital stock had fallen 18% over the prior month. <\/p>\n Micron stock sits up 237% year to date, but the memory\/storage group as a whole has been working its way out of a rough few weeks. Today’s gains represent a bounce off of recent volatility, and that framing matters for how investors size their positions. <\/p>\n Seagate stock joining the move is notable. It broadens the story from a NAND flash bid into the full storage stack, hard drives included, with Seagate CEO Dave Mosley recently citing “durable long-term demand for mass capacity storage” as AI accelerates data generation. <\/p>\n The SanDisk-SK Hynix Link <\/p>\n The day’s two strongest names are also linked commercially. On August 3, SanDisk and SK Hynix announced a collaboration on High Bandwidth Flash (HBF), a technology aimed at AI inference workloads that require far more memory capacity than current architectures deliver. <\/p>\n The Roundhill Memory ETF captures this basket in one line. Per its fact sheet dated May 11, the DRAM ETF’s top positions were Samsung Electronics at 25%, SK Hynix at 24.2%, and Micron at 23.8%, with SanDisk at 4.7% and Seagate at 4.5%. The fund’s expense ratio is 0.65%. <\/p>\n What to Watch Now <\/p>\n A single-day rally doesn’t necessarily mean the bulls will continue to charge ahead. Investors can watch for whether the Korea-led bid carries into Friday’s Seoul session, whether Seagate and the hard-drive side keep pace with the flash names, and whether this group can close the month-long gap it’s still climbing out of. <\/p>\n A cohort that just fell 20% in a month can move violently in both directions. Position sizing should reflect that volatility, even as the AI-driven demand narrative continues to firm. The next anticipated indicator arrives with Friday’s Asia session and, further out, Micron’s Q4 FY2026 report. <\/p>\n Act now: the analyst who called NVIDIA in 2010 just named his top 10 AI stocks \u2014 and Western Digital didn’t make the cut. Grab the names FREE today<\/a>. <\/p>\n<\/a> Thinkstock <\/p>\n