Parallel approval process allows specifying multiple approvers simultaneously.

When you select multiple approvers, then we have to choose any one of the following:

    a. Approve or reject based on the FIRST response.
    b. Require UNANIMOUS approval from all selected approvers.

The approver setting could be set to unanimous or first action. In Require UNANIMOUS approval from all selected approvers parallel approval process, all the approvers must approve a request, before it is considered as approved. But in case of Approve or reject based on the FIRST response, anyone of the Approvers can respond.

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