Leaders in Marketo are assigned leader identifiers in a sequential order, starting with 1. Using Get Multiple Lines by Endpoint API of a REST filter type filter , you can request 300 leads by the identifier of the leader with each call.
You need to specify id as filterType and input identifiers as filterValues ββwith every call to this endpoint. To get all the results, you will iterate over the total number of potential customers 300 at a time.
The first API call will (replace ... with all the values ββin between):
/rest/v1/leads.json?filterType=Id&filterValues=1,2,3,...,298,299,300
The second API call, and each subsequent API call will follow the same pattern:
/rest/v1/leads.json?filterType=Id&filterValues=301,302,303,...,598,599,600
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