Dot-walked conditions that use the IS NOT operator are always evaluating to True on Data Policies.

 

1. Log in to the demo instance.
2. Navigate to Service Catalog > Tasks.
3. Select TASK0000002.
4. Note that the item on the associated Request item is Blackberry.
5. Right-click the header, and select Personalize > Data Policies.
6. Click New.
7. Enter the condition: [Request item.Item] [IS NOT] [Blackberry]
8. Right-click the header and Save.
9. Go to the Data Policy Rules Related list, and click New.
10. Set the field name to Work notes, and set Mandatory to True.
11. Click Submit.
12. Navigate back to TASK0000002.
    Note that Work notes is now Mandatory, even though the Request item.Item is Blackberry.

Create a script to populate the value of the dot-walked field on the current record, and evaluate on this rather than dot walking.

Alternatively, you can use an IS ONE OF operator and reference all the records except the one you want to exclude. The downside of this option is that it requires additional maintenance whenever further options are added.