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You want to purchase Risk Register for Jira Cloud, but only a small subset of users intend to use it; can you license the product just for the small subset of users?
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How is the license volume determined?
The Marketplace requires that you purchase a license for an add-on, any add-on, that is commensurate with the license of the hosting Atlassian product. If you have a licenses for more than one Atlassian product, the largest of those licenses applies; for example, suppose you have:
- 25 Core users; and
- 100 Software users; and
- 3 Service Desk agents;
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For Jira, you must purchase the app license that matches the highest Jira application tier. For example, if you have a 500-User Jira Software license, and a 20-Agent Jira Service Management license, your Jira apps must be at the 500-User level. – "Which license do I choose when purchasing an app?"
More information
Atlassian has a post about it here: Licensing add-ons: Can I purchase an add-on for only subset of my users?