You must specify the winning lead ID and the losing lead ID. Also, specify if you want to merge the leads in the CRM. When you run the mapping, the Marketo API deletes the losing lead ID and adds the data from the losing lead ID to the winning lead ID. The Marketo API adds the data only if the winning lead ID field does not have any data, but does not overwrite the winning lead ID data.

For example, you have data for similar leads and you want to merge that data. The source is a flat file source that contains the following lead IDs and the value for the merge in Customer Relational Management (mergeinCRM) as TRUE.

You must designate the winning lead and a losing lead with the following convention:

Id, leadid, MergeInCRM

1,2,True

In the flat file, Id is the winning lead column and leadid is the losing lead column.

Configure a task and select the update operation. Select the flat file as the source and MergeLead as the target object and run the task. The attributes of the winning lead take precedence. In the example, the losing lead ID is 2 and the winning lead ID is 1. The Marketo API deletes the lead with ID 2.

You can merge more then one losing leads with a winning lead.

For example, designate the winning lead and losing leads with the following convention in a flat file before you configure the update operation:

"id","leadId","mergeInCRM"
"18660653","18660660,18660661","true" 

In the example, the losing lead IDs are 18660660 and 18660661 and the winning lead ID is 18660653.