The “Sent Messages” page displays all the messages you sent over time to users in your account and which you have not deleted.
When a message is sent to multiple users, one message is created for each recipient. Hence, you can see when each recipient opened and deleted his/her message.
If you choose to send an e-mail to each recipient (“Send email notification to recipients” is selected by default), each individual will receive an e-mail and there will be no CC’s or BCC’s.