A board is restricted to the users by shares of the filter on which the board is defined. In your case the board can be used by users who have access to mentioned projects.
You can read about restricting access to board here:
If you do not want the users of the projects use the board or the filter then do not share the filter with them
The Jira Marketing team is putting together an ebook on migrating to Data Center. We're looking for pro tips on how you staffed your project team and organized your Proof of Concept. Share yo...
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