How do I automatically add other email respondents as request participant

[Ben]

Situation: We have people that send an email to our Service Management board, and copy in 3rd parties.

• It is possible the sender won’t be a customer
• The people who are copied in are likely to not be customers yet.
• Those that are copied in might be in either the TO box or the CC box

My goal is to ensure everyone in the email conversation (From, To, CC) is included in the request. What is the best way to do this?