Hi , 

for anyone transitioning from Zendesk to JSM this is a missing feature that creates many problems internally. 

We need the ability to put anyone (even non-registered Jira users) as requested participants. Something like "CC" fields in emails, so they start getting notifications on tickets. 

The reason behind this is that there are certain groups of people within customer organizations that need to be in the loop on one specific issue but all of them are, for instance, members of the one email distribution list. Thus the need to send email updates to these distribution lists or persons without any restrictions. 

Zendesk introduced this a year ago and it was a real hit. You should think about it too. Ty