What is metadata? The most basic definition is that metadata is “data about data,” but this does not give practitioners much guidance. A better definition is that metadata is information associated with—and made part of—an electronic document that is not visible in the normal viewing or printing of that document. Examples include a document's file creation date, the file's location, the document's author, the word count, tracked changes and comments.

Lawyers can use metadata during the e-discovery process to more efficiently search for relevant documents. For example, by relying on document timestamps, you can set date and time restrictions to narrow the scope of your collection. Metadata can be used to authenticate documents, particularly if a case goes to trial. Metadata also provides timelines for electronically stored information (ESI). For example, if a case requires you to show the evolution of a contract over time, metadata can enable you to do that. It also can help you identify custodians who may have sent, received or made changes to a particular document.

Chief U.S. Magistrate Judge Paul W. Grimm noted in Lorraine v. Markel American Ins. Co., 241 F.R.D. 534 (D.Md. May 4, 2007) that the presumption that metadata is not hearsay and is prima facie evidence of authenticity. Further, embedded metadata provides an understanding of electronic documents, and is generally discoverable and should be produced as a matter of course.