Private Permission of Itemtype depend on classification of ItemType

You may not need a 'Private' permission. It sounds like you want a regular permission but applied to a subset of items within an item type. In that case, in the past, we have used the lifecycle map to set the permission. You would add the permission to the item type permissions, and then create a separate lifecycle map associated with this itemtype. The benefit to that is that Innovator allows you to set the lifecycle based on classification (not permission). The first state (and only state, if you wish) of the lifecycle can have the 'Permission' property set to your restricted permission. Another option would be to allow all the creators/editors of the item type to update the permission within the default permission, then create a server method that sets permission id based on classification onBeforeUpdate. You must ensure that the user that might update the classification or add the item can change from the default to use this option, which would allow savvy users to change permissions on items which do not meet your classification requirements. That is why we typically use a separate lifecycle to set permissions. I hope this helps.

You may not need a 'Private' permission. It sounds like you want a regular permission but applied to a subset of items within an item type. In that case, in the past, we have used the lifecycle map to set the permission. You would add the permission to the item type permissions, and then create a separate lifecycle map associated with this itemtype. The benefit to that is that Innovator allows you to set the lifecycle based on classification (not permission). The first state (and only state, if you wish) of the lifecycle can have the 'Permission' property set to your restricted permission. Another option would be to allow all the creators/editors of the item type to update the permission within the default permission, then create a server method that sets permission id based on classification onBeforeUpdate. You must ensure that the user that might update the classification or add the item can change from the default to use this option, which would allow savvy users to change permissions on items which do not meet your classification requirements. That is why we typically use a separate lifecycle to set permissions. I hope this helps.