Intermediate → Expert
Market structure · NBBO lite
National best bid and offer as a consumer-protection vocabulary word. Education only — not a recommendation to buy, sell, or hold anything.
NBBO in one line
NBBO — national best bid and best offer across protected quotes in U.S. NMS stocks (simplified). It is a reference for “best displayed prices,” not a promise of your fill.
Why venues multiply
- Exchanges and other trading centers compete.
- Orders route; speed and fees differ.
What NBBO is not
- Not a guarantee you get mid-price.
- Not applicable identically to every asset class (options, OTC, crypto differ).
- Not investment advice.
Literacy use
When you see a quote, ask: is this a protected NBBO-style reference, a single-venue quote, or an indicative mark?
Practice tip: Delayed educational marks live on /charts/ and delayed marks.