The set of documents (including electronically stored information (ESI)) that counsel must review for relevance or responsiveness to a request for documents, subpoena, or Freedom of Information Act (FOIA) request.

Often, counsel do not review every document they collect from their client. Instead, counsel use processes like data filtering to identify and exclude documents that they reasonably expect are irrelevant to the litigation. After counsel identifies and eliminates documents that they do not need to review, the remaining documents comprise the review set.