Instrument Catalog
2 shownOne master row per distinct contract -- every position that trades AAPL's $300 call expiring 2027-01-15 points at the same row here instead of each embedding its own copy of its strike, expiry, and exercise style. Each one has a stable, lookupable code: the standard OCC option symbol (root ticker + expiry + call/put + strike) for options, or just the ticker for stock.