Smart card system and methods for proving dates in digital files

A method of maintaining trust in the content of a digital data file, comprising:

• providing a trusted time source to provide a certifiable time for an unalterable time stamp, wherein said certifiable time confirms at least one of said file's access, creation, modification, receipt, or transmission;
• receiving a request to save the file from a user;
• saving the file at a moment in time;
• retrieving from said trusted time source a date and a time corresponding to said moment in time, wherein said moment in time is substantially the current time at said trusted time source corresponding to receipt of said request;
• appending said date and said time retrieved from said trusted time source to said saved file;
• signing said saved file with said date and said time retrieved from said trusted time source appended thereto;
• hashing said signed file to produce a digest;
• signing said digest with a key to produce a certificate;
• appending said certificate to said saved file;
• and
• saving said file with said certificate appended thereto.

Apparatus for maintaining trust in the content of a digital data file, comprising:

• computing means, including a central processing unit (CPU), means for storing an operating system that is adapted to control the CPU, the plurality of digital data files, one or more applications programs for accessing, creating, modifying, and transmitting the plurality of digital data files, and means for controlling storage and retrieval of the plurality of digital data files to and from said storage means;
• and
• fraud prevention means, operatively coupled to said computing means, said fraud prevention module including:
• a trusted time source to provide a certifiable time for an unalterable time stamD wherein said certifiable time confirms at least one of said file's access, creation, modification, receipt, or transmission;
• means for receiving a request to save the file from a user;
• first means for saving the file at a moment in time;
• means for retrieving from said trusted time source a date and a time corresponding to said moment in time, wherein said moment in time is substantially the current time at said trusted time source corresponding to receipt of said request;
• first means for appending said date and said time retrieved from said trusted time source to said saved file;
• first means for signing said saved file with said date and said time retrieved from said trusted time source appended thereto;
• means for hashing said signed file to produce a digest;
• second means for signing said digest with a key to produce a certificate;
• second means for appending said certificate to said saved file;
• and
• second means for saving said file with said certificate appended thereto.