You want to include employees in an e-mail blast.
SAP Cloud for Customer
If the Include Employees box is not checked, employees will not be included.
In the E-mail Blasts dialog, set the flag for Include Employees to allow marketing administrators to send e-mail blasts to employees listed in a target group. When you select this flag, the e-mail blast that will be sent out includes target group members (accounts, individual customers, contacts, etc) as well as the employees listed under the Employees tab screen.
SAP Administrator Guide - Configuring Target Groups
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