Ancillary Outputs are post-processing steps applied to assembled documents after the document is rendered. They are applied on a request to generate documents (and apply to all documents generated as part of the request) or as part of a DocumentSet object to apply the instructions to each specific document generated as part of the request.
The AncillaryOutputOptions are submitted in the Generate, SelectAndGenerate, and SelectGenerateDeliver operations to apply to all documents generated. They are submitted as part of the DocumentSet in the Generate, SelectAndGenerate, and SelectGenerateDeliver operations to apply on a document-by-document basis. To apply multiple post-processing events to a document or document set, you must submit a unique AncillaryOutputOptions object on the request (so that a single request might contain multiple AncillaryOutputOptions objects.