In Summer ’21, Salesforce bringing you an entirely new way to manage your org’s access control. Introducing restriction rules, an easy-to-manage sharing feature that lets you grant record access in a secure, granular way. Simply pick which users should see which subset of records, and that’s it!

If you have users that should only have access to a specific subset of records, restriction rules provide another layer of security that you can layer on top of your existing org-wide defaults, sharing rules, and other settings. Restriction rules also allow you to configure your access so that custom objects, contracts, tasks, and events are completely “Private,” even for users with access to related accounts, which previously wasn’t possible.

Restriction Rules Developer Guide

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