The sharing rule is a tool that will open accessibility to records that users do not own. The sharing rule will open a lateral, flexible sharing that will complete role hierarchies.
It is possible to share records based on their ownership or based on criteria (value of fields) and to share these records with public groups, roles and roles-and-subordinates. Finally, access to these records can be defined: read-only or read/write. It is thus necessary to define the “What”, the “With whom” and the “How”.
If organization-wide defaults (OWD) are public read/write (in other words, visibility is open), it is not necessary to open additional access to records.
You can create up to 300 sharing rules per object, including 50 criteria-based sharing rules.
Ownership -based sharing rule example: A wants to share the opportunities owned by the sales representative of the EMEA sector with the public group of sales representatives in read-only.
Criteria-based sharing rule example: A wishes to share the opportunities “In progress” with the Vice President of international sales, in read/write.