Hi,
You have not provided information from where the screenshot is but as I have found out you are looking at policy initiative (policy definition set). Policy initiatives are basically separate policies (policy definitions) that are grouped so you can do single policy assignment and get compliance for all of them under one assignment. Policy initiatives can be built-in or custom ones. The one that are built-in they only group built-in policies and these cannot change. If you create your own custom policy initiative you can provide whatever values you want for reference ID for each policy that is part of your initiative. So you can change that property only if you have custom policy and you can specify that property only on initial creation as one specified cannot be changed without removing the policy from the initiative.
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