Facebook destination activating multiple emails, increases audience match rate at Facebook?

[Ankita05]

We are having multiple emails present for a single records from different sources coming into AEP, Now if we map multiple emails(eg. email 1 & email2) from AEP to Facebook target attribute (email_lc_sha256) does it increase the match rate at Facebook ?

We are not certain if

1. only one email will be picked up at Facebook destination

2. Both emails will be sent out to Facebook or

3. One email overwrites the other?

Your inputs are really appreciated!

Thanks in advance. 

[Anil_Umachigi · Accepted solution]

@Ankita05 All of this depends on how "Segments" are set up, since you send a segment to facebook. 

Segments are driven by merge policy set up. 

Merge policies are rules used by Profile to determine how data will be prioritized and combined into a unified view under certain conditions.
If a merge policy is not defined, the default Platform merge policy is used. If you would rather use a merge policy specific to your organization, you can create your own and mark it as your organization’s default.

When the data from multiple sources conflicts (for example one fragment lists the customer as “single” while the other lists the customer as “married”) the merge policy determines which information to include in the profile for the individual.

Read in details here, and review how merge policy is set up to help answering your question.