GameStop. The fortnight a subreddit executed the most public short squeeze in market history and every system this archive tracks — market microstructure, platform incentives, mob coordination, clearing-house plumbing — collided in one ticker. The mechanics, filed properly: WallStreetBets identified that GameStop was shorted beyond 100% of its float (an over-leveraged position visible in PUBLIC data), coordinated a buy-and-hold spiral with meme-grade conviction (“diamond hands,” rocket emojis as consensus protocol), and drove the stock from ~$20 to an intraday ~$483, detonating a hedge fund (Melvin, bailed out mid-squeeze) and briefly making the joke stock worth more than half the S&P’s members. Then the infrastructure spoke: ROBINHOOD — the retail platform whose whole brand was democratized access — RESTRICTED BUYING (sell-only!) at the squeeze’s peak, and the conspiracy theories wrote themselves until the mundane truth emerged, which this blog appreciated alone in a crowd screaming about villains: CLEARING-HOUSE COLLATERAL REQUIREMENTS. Two-day settlement (T+2) means Robinhood fronts risk on every trade for 48 hours; the volatility spiked their deposit requirement TENFOLD overnight (a multi-billion-dollar margin call at 5am); and restricting buys was the position-limiting move available. The plumbing nobody knew existed became the story everyone got wrong (#178’s oil-contango lesson: the price is a fact about the MECHANISM — and the mechanism has capacity limits, #022, always, everywhere, forever).
The aftermath queue: congressional hearings scheduled, T+1 settlement suddenly on the industry roadmap (a decade of “someday” converted to “soon” by one week of memes — incidents drive modernization, #123), and the deeper file: coordination costs collapsed (a million retail traders synchronized FOR FREE via memes — #187’s positional-leverage doctrine, now retail-shaped), while payment-for-order-flow’s conflicts got their first mainstream vocabulary lesson. Nobody in the stack was neutral; everyone’s incentives were suddenly legible. The market survived being understood, barely.
TIL: T+2 settlement and NSCC deposit formulas — the actual math of why the buying stopped. The most important system is always the one you learn exists during its worst week (#178, #197, the archive’s entire epistemology in one pattern).