American Depositary Receipt (ADR): A U.S.-traded certificate representing shares of a foreign company, issued by a depositary bank that holds the underlying stock abroad—allowing American investors to buy foreign equities in dollars, on U.S. exchanges, with U.S. settlement and disclosure standards. SK Hynix’s July 10 debut turned this normally sleepy corner of market plumbing into the week’s headline event. The South Korean memory giant priced its ADRs at $149, raising $26.5 billion—the largest U.S. listing ever by a foreign company—and opened at $170 for a 14% first-trade pop after the order book ran more than seven times oversubscribed. The mechanics matter for understanding what investors actually bought. Each ADR represents a claim on ordinary SK Hynix shares held in custody in Seoul; the depositary bank converts dividends from won to dollars and passes through corporate actions. ADRs trade independently of the home-market listing during U.S. hours, so price gaps between the Korean shares and the U.S. receipts can open and close via arbitrage. Companies pursue U.S. listings of this scale for three reasons, all visible in SK Hynix’s case: access to the deepest capital pool in the world (the $26.5 billion funds fabs and equipment for AI memory expansion), a valuation currency benchmarked against U.S. peers like Micron rather than the discounted Korean market, and index eligibility that unlocks passive flows. The timing was strategic—SK Hynix is the world’s largest producer of the high-bandwidth memory that feeds Nvidia and AMD accelerators, and it listed directly into the “memory mania” trade weeks after Micron’s blowout quarter, effectively arbitraging peak U.S. enthusiasm for its sector. The risks run both directions. For the company, a U.S. listing means SEC-grade disclosure, litigation exposure, and a shareholder base that punishes guidance misses far faster than home markets. For investors, ADRs carry currency risk (a weakening won erodes dollar returns even if the business performs), home-market political risk, and the possibility that the U.S. premium fades once index inclusion flows are absorbed—the pattern seen in several prior mega-listings. The seven-times oversubscription and instant 14% premium signal that, for now, U.S. capital wants direct exposure to the AI memory supply chain at almost any structural cost. Whether SKHY holds above its debut range will be an important tell on the durability of the entire memory trade.