Although you can request multiple markets from listMarketBook, there are limits on the amount of data requested in one request.
The following table explains the "weighting" of data for each MarketProjection. If you exceed the maximum weighting of 150 points, the API will return a TOO_MUCH_DATA error
| MarketProjection | Weight |
|---|---|
MARKET_DESCRIPTION | 2 |
RUNNER_DESCRIPTION | 2 |
| EVENT | 2 |
| EVENT_TYPE | 2 |
| COMPETITION | 2 |
| SP_AVAILABLE | 2 |
| SP_TRADED | 5 |
| EX_BEST_OFFERS | 3 |
| EX_ALL_OFFERS | 15 |
| EX_TRADED | 15 |