# Policy Certifications and Diffs

## Required permissions

To manage and apply existing policies to data sources, a user must have either the CREATE\_DATA\_SOURCE Immuta permission or be manually assigned the owner role on a data source.

## Create a custom certification for a global policy

Data governors can add certifications that outline acknowledgements or [require approvals from data owners](#certify-global-policies). For example, data governors could add a custom certification that states that data owners must verify that tags have been added correctly to their data sources before certifying the policy.

1. Click **Add Certification** in the data policy builder.
2. Enter a **Certification Label** and **Certification Text** in the corresponding fields of the dialog that appears.
3. Click **Save**.

## Certify global policies

After a policy with a certification requirement is applied to a data source, data owners will receive a notification indicating that they need to certify the policy.

1. Navigate to the **Policies** tab of the affected data source, and review the policy in the **Data Policies** section.
2. Click **Certify Policy**.
3. In the **Policy Certification** modal, click **Sign and Certify**.

## View policy diffs

Once you have a data policy in effect, you can view the changes in your policies by clicking the **Policy Diff** button in the data policies section on a data source's policies tab.

The **Policy Diff** button displays previous policies and the current policy applied to the data source.