Practical Law Glossary Item w-003-3374 (Approx. 3 pages)
Glossary
Hash Value
An alpha-numerical identifier (digital fingerprint) that is unique to each electronic file. A hash value does not appear on the face of a document or file but is part of the file's metadata. MD5 and SHA are common types of hash values.
Documents with matching hash values are exact duplicates. Accordingly, counsel often use hash values to de-duplicateelectronically stored information (ESI). However, hash values are susceptible to corruption during ESI collection. An ESI collector who is not skilled and careful may alter a file's hash value during collection and render de-duplication by hash value ineffective.
Because ESI produced as native filesdo not have Bates numbers stamped on the documents, counsel sometimes use hash values to identify each produced file.