Date-provable registration system for published documents

Abstract

A system and method are disclosed for rendering published documents tamper evident. Embodiments render classes of documents tamper evident with cryptographic level security or detect tampering, where such security was previously unavailable, for example, documents printed using common printers without special paper or ink. Embodiments enable proving the date of document content without the need for expensive third party archival, including documents held, since their creation, entirely in secrecy or in untrustworthy environments, such as on easily-altered, publicly-accessible internet sites. Embodiments can extend, by many years, the useful life of currently-trusted integrity verification algorithms, such as hash functions, even when applied to binary executable files. Embodiments can efficiently identify whether multiple document versions are substantially similar, even if they are not identical, thus potentially reducing storage space requirements.

1 . A computer-implemented document integrity verification method comprising:
 receiving a digital document in a word processing format into a non-transitory computer readable medium;   generating a first baseline data sequence from the digital document;   generating a first modified baseline data sequence from the first baseline data sequence in accordance with a set of modification rules, wherein at least one element of the first baseline data sequence, between the first and final elements of the first baseline data sequence, is modified in the first modified baseline data sequence, and wherein an integrity verification code (IVC) generated for the first modified baseline data sequence will differ from an IVC generated for the first baseline data sequence;   generating a first original IVC, wherein generating a first original IVC comprises performing a one-way operation on the first modified baseline data sequence, and wherein the modification rules render tampering undetectable for the at least one modified element within the first baseline data sequence; and   transmitting the first original IVC across a public computer network to a remote database node.   
     
     
         2 . The method of  claim 1  further comprising:
 publishing the digital document with at least a portion of the first original IVC rendered on a face of the published document. 
 
     
     
         3 . The method of  claim 1  further comprising:
 printing the document on paper. 
 
     
     
         4 . The method of  claim 1  further comprising:
 determining whether a trigger condition has been satisfied; and 
 in response to determining that the trigger condition has been satisfied, beginning the generation of the first baseline data sequence. 
 
     
     
         5 . The method of  claim 4  wherein the trigger condition comprises the document being sent to a monitored destination selected from the list consisting of a printer and an email inbox. 
     
     
         6 . The method of  claim 1  further comprising:
 generating a second original IVC for at least a portion of the digital document. 
 
     
     
         7 . The method of  claim 6  further comprising:
 transmitting the second original IVC with the first IVC in a single database entry to the remote database node. 
 
     
     
         8 . The method of  claim 6  wherein generating the second original IVC comprises:
 generating a second modified baseline data sequence from at least a portion of the digital document in accordance with a set of modification rules, wherein the first original IVC is used to select portions from the digital document for inclusion in or exclusion from the second modified baseline data sequence. 
 
     
     
         9 . The method of  claim 1  further comprising:
 transmitting a security code to the remote database node. 
 
     
     
         10 . The method of  claim 1  further comprising:
 transmitting a user identification to the remote database node. 
 
     
     
         11 . A computer program embodied on a computer executable medium and configured to be executed by a processor, the program comprising:
 code for receiving a digital document in a word processing format into a non-transitory computer readable medium;   code for generating a first baseline data sequence from the digital document;   code for generating a first modified baseline data sequence from the first baseline data sequence in accordance with a set of modification rules, wherein at least one element of the first baseline data sequence, between the first and final elements of the first baseline data sequence, is modified in the first modified baseline data sequence, and wherein an integrity verification code (IVC) generated for the first modified baseline data sequence will differ from an IVC generated for the first baseline data sequence;   code for generating a first original IVC, wherein generating a first original IVC comprises performing a one-way operation on the first modified baseline data sequence, and wherein the modification rules render tampering undetectable for the at least one modified element within the first baseline data sequence;   code for transmitting the first original IVC across a public computer network to a remote database node.   
     
     
         12 . The program of  claim 11  further comprising:
 code for printing the digital document with at least a portion of the first original IVC rendered on a face of the published document. 
 
     
     
         13 . The program of  claim 11  further comprising:
 code for determining whether a trigger condition has been satisfied, and in response to determining that the trigger condition has been satisfied, beginning the generation of the first baseline data sequence. 
 
     
     
         14 . The program of  claim 13  wherein the trigger condition comprises the document being sent to a monitored destination selected from the list consisting of a printer and an email inbox. 
     
     
         15 . The program of  claim 11  further comprising:
 code for generating a second original IVC for at least a portion of the digital document. 
 
     
     
         16 . The program of  claim 11  further comprising:
 code for transmitting the second original IVC with the first IVC in a single database entry to the remote database node. 
 
     
     
         17 . The program of  claim 16  wherein generating the second original IVC comprises:
 generating a second modified baseline data sequence from at least a portion of the digital document in accordance with a set of modification rules, wherein the first original IVC is used to select portions from the digital document for inclusion in or exclusion from the second modified baseline data sequence. 
 
     
     
         18 . The program of  claim 11  further comprising:
 code for transmitting a security code to the remote database node. 
 
     
     
         19 . The program of  claim 11  further comprising:
 code for transmitting a user identification to the remote database node. 
 
     
     
         20 . A document integrity verification apparatus comprising:
 processor;   a memory comprising a non-transitory computer readable medium; and   a modified IVC generator configured to:
 receive a digital document in a word processing format into the medium; 
 generate a first baseline data sequence from the digital document; 
 generate a first modified baseline data sequence from the first baseline data sequence in accordance with a set of modification rules, wherein at least one element of the first baseline data sequence, between the first and final elements of the first baseline data sequence, is modified in the first modified baseline data sequence, and wherein an integrity verification code (IVC) generated for the first modified baseline data sequence will differ from an IVC generated for the first baseline data sequence; and 
 generate a first original IVC, wherein generating a first original IVC comprises performing a one-way operation on the first modified baseline data sequence, and wherein the modification rules render tampering undetectable for the at least one modified element within the first baseline data sequence.