I have been sealing digitally for years utilizing a CAD block of the seal with a p-line signature. This file is stored in a secure directory, moved to another directory where it expires shortly after printing. I x-ref the file into the document and then generate .dwf or .pdf prints. Authentication could be added in the Adobe software or with any plug-in. I use this system so the data is resident in the file and not dependent upon a third party program that may or may not be there in the future. While authentication in .pdf is rising in popularity we prefer the .dwf format for review/redline in Autodesk Design Review, and occasionally digital submittals. The requirements for professional control are met with the seal secured, only placed by architects and auto-deletion shortly after placement. It isn't perfect but it is efficient and avoids repeat activity on those 80 sheet sets and re-plots or re-seals are a breeze.
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Kevin Evernham AIA
Director of Architecture
AAD:FITCH, Inc.
Scottsdale AZ
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