A $470 billion rout in just a little over a month has flipped SK Hynix Inc. from one of the world's hottest AI trades to one of the biggest portfolio question marks.

The dramatic selloff underscores growing investor anxiety about the sustainability of the memory-chip boom that has powered semiconductor stocks to record highs. SK Hynix, a key supplier of high-bandwidth memory essential for AI accelerators, saw its market valuation plummet as concerns mount over oversupply and weakening demand.

The reversal highlights the volatile nature of semiconductor cycles, where rapid shifts in sentiment can erase months of gains in weeks. Market participants are now reassessing whether the AI-driven demand surge can sustain elevated pricing for memory chips amid signs of inventory buildup at major customers.