Assigne users which can not login

[Antonio Mark]

I have a Jira instance where I want to synchronize some information with a 3rd party system. 
The information to synchronize also contains users assigned to issues.

In Jira I want to assign users to an issue and sync this back to the 3rd party system. Not all user assigned to an issue need to login in to Jira so I don't want to use the licences for this users. I've tried to create inactive users but these can not be assigned to issues. Also I have tried to remove the "jira-users" group (which is linked to Jira access) from the users group, but than I also can not assign this user to an issue.

Is there a way to create a user which can not login to jira and does not use up the licences for this instance but can be assigned to an issue?

[Jack · Accepted solution]

If your question is about licensed users versus non-licensed users then to answer that question in a user that will be assigned to an issue must be licensed. If your question is about how to integrate to a third-party application several options exist: APIs, web hook, email.