...
Verity Support will notify the customer to confirm partner that the custom segment is active. The additional segments field will be included in each Verity JSON response. The segment field will list the names of any custom segments matching the analyzed content. The Custom Segment analysis:
Is set up per client partner API authentication key (specified by the x-api-key in the HTTP header of the analysis request).
Applies to all requests from the same client partner API authentication key.
Continues until the client partner emails Verity Support to deactivate the custom segment.
Ignores any categories where a value is not specified in the Custom Segment Request form.
...