Abstract: Techniques are described for tracking documents within an office or network based on unique metadata keys generated for the documents. The disclosed techniques include generating a key for a document based on metadata extracted from the document, associating the key representing the document with one or more master files that include the document, and then applying the key to the document. To track a lost or disassociated document, the disclosed techniques include either generating the key from the document or reading the key previously applied to the document, and then using the key to re-associate the document with the one or more master files that include the document. According to the disclosed techniques, a metadata key may comprise a series of symbols constructed so as to maintain its aspect ratio or spacing regardless of manipulation of the document to which the key has been applied.