05422953 is referenced by 149 patents and cites 7 patents.

A personal data/time notary device is embodied in a token device such as a "smart card". The portable notary device includes an input/output (I/O) port, which is coupled to a single integrated circuit chip. The I/O port may be coupled to a conventional smart card reading device which in turn is coupled to a PC, lap-top computer or the like. A tamper resistant secret private key storage is embodied on the chip. The private key storage is coupled to the processor which, in turn, is coupled to a permanent memory that stores the program executed by the processor. At least one clock is embodied on the card. A second clock 14 and a random value generator 10 are also preferably coupled to the processor. The device combines digital time notarization into a digital signature operation to ensure that a time stamp is always automatically present. The user does not need to be involved in any additional decision making as to whether time stamping is necessary.

Title
Personal date/time notary device
Application Number
8/56547
Publication Number
5422953
Application Date
May 5, 1993
Publication Date
June 6, 1995
Inventor
Addison M Fischer
60 14th Ave. South, Naples, 33942
FL, US
Agent
Nixon & Vanderhye
IPC
H04K 1/00
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