 Efforts to redact similarly petrified PDF files have resulted in the removal of redacted layers and exposure of redacted information, such as social security numbers and other private information.Traditionally, electronic discovery vendors had been contracted to convert native files into TIFF images (for example 10 images for a 10-page Microsoft Word document) with a load file for use in image-based discovery review database applications.Increasingly, database review applications have embedded native file viewers with TIFF-capabilities.