A document management system includes a memory for storing machine-readable code and a processor configured to execute the machine-readable code. The processor stores a first document, a first hash of the first document, and a first key in the memory. The first document is encrypted with the first key. The processor further receives a request for the first key. The request includes a second hash of a second document where the second document is purported to be a copy of the first document. The processor further compares the first hash to the second hash and sends the first key in response to the request when the first hash matches the second hash.