> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/getting-started/subscription-types/quotes.md).

# Quotes

Subscribe to `QUOTES` to receive top-of-book, or best bid and offer (BBO), updates. Each `marketUpdate` includes the current bid and offer price, quantity, and order count.

Use BBO updates to track the best available prices and displayed liquidity. The following updates show changes for December Corn.

### Best bid and offer message examples

```protobuf
marketUpdate {
  marketId: 1596974561793814014
  transactionTime: 1634157040305588641
  marketSequence: 3197957
  bbo {
    bidPrice: 511250000000
    bidQuantity: 9
    bidOrderCount: 3
    offerPrice: 511250000000
    offerQuantity: 10
    offerOrderCount: 4
  }
}

marketUpdate {
  marketId: 1596974561793814014
  transactionTime: 1634157219716391027
  marketSequence: 3197960
  bbo {
    bidPrice: 511250000000
    bidQuantity: 9
    bidOrderCount: 3
    offerPrice: 511250000000
    offerQuantity: 12
    offerOrderCount: 5
  }
}

marketUpdate {
  marketId: 1596974561793814014
  transactionTime: 1634157251821302183
  marketSequence: 3197962
  bbo {
    bidPrice: 511250000000
    bidQuantity: 12
    bidOrderCount: 4
    offerPrice: 511250000000
    offerQuantity: 12
    offerOrderCount: 5
  }
}

marketUpdate {
  marketId: 1596974561793814014
  transactionTime: 1634157335536570197
  marketSequence: 3197964
  bbo {
    bidPrice: 511250000000
    bidQuantity: 12
    bidOrderCount: 4
    offerPrice: 511250000000
    offerQuantity: 13
    offerOrderCount: 6
  }
}
```


---

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