×

Self validating security documents utilizing watermarks

  • US 6,970,573 B2
  • Filed: 11/09/2001
  • Issued: 11/29/2005
  • Est. Priority Date: 08/09/1995
  • Status: Expired due to Fees
First Claim
Patent Images

1. A security document for a user, said security document having multiple fields, a plurality of said fields containing hidden watermark data, the data in at least one of said fields identifying a physical characteristic of said user, the hidden data in at least two of said fields being coordinated such that if the data in one of said fields is changed without changing the other of said fields it will indicate that said security document has been altered.

View all claims
  • 7 Assignments
Timeline View
Assignment View
    ×
    ×