I found this JIRA ticket, but it appears still open with a vague commitment that the work would be done, but that was about 1.5 years ago: https://jira.atlassian.com/browse/JRA-4505
Our company is growing and we were also acquired by another company that does not yet use Jira, although they are interested. The best scenario for me would be to set up permission schemes based on project categories and categories can be set to cover the two different company's, other subsidiaries, and specific departments.
Does anyone know if this is possible?