Three types of data security in Siebel:
1. Restrict the access to the data only to the owner.
2. Assign a team to the records. Allow the team members view the records
3. Assign an organization to the records.
For case 1 ad 2, you can grant the access to a user or to a position.
A position is a job title associated with an organization. A manager position can have sub-ordinate positions to form a manager hierarchy. A position can report to a single position.
A position in Siebel is almost the same as the position in E-Business Suite HR. However, they are created for different purposes. The position in EBS HR is mainly for head count budgeting and many EBS HR apps deployments do not use the feature. Using position for security has a major benefit is to keep the data security rule independent from the individuals.