E-Discovery Update: To Globally Dedupe Or Not ... That Is The Question

When lawyers are asked by a document review vendor whether they want to dedupe "globally" or "by custodian," they may not appreciate the difference between the two methods and the impact to the case, in terms of both discovery costs and consistency of treatment of documents in the review.

Deduping globally means that exact duplicate families are removed from the document review population. A "family" refers to a parent document (such as an e-mail) with attachments. Documents dedupe out of the review population only if the entire family is an exact duplicate match. It is common when collecting data from multiple employees at a company to have a high rate of exact duplicates in the data set because, for example, employees often copy multiple people on e-mails, so each of those employees would have the same e-mails in their "in box."