What about more fine-grained permissions, such as blocking changes to release objects?

[Dennis Kornbluh]

This question is in reference to Atlassian Documentation: Global Permissions

Is JIRA Portfolio capable of controlling update access to specific objects, such as releases? We are trying to manage change in a large team, and date changes to releases should be restricted to a few stakeholders.

[Boris Berenberg]

You can not do permissions on a per object basis. You can set people as editors or viewers as described at: https://confluence.atlassian.com/display/JIRAPortfolioServer/Permission+Settings