Document copy authentication
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United States of America Patent
Stats
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Oct 20, 1992
Grant Date -
N/A
app pub date -
Dec 19, 1991
filing date -
Dec 19, 1991
priority date (Note) -
In Force
status (Latency Note)
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Abstract
A system for authenticating a hard copy of an original document. The system employs a special copying machine at the sender's end together with a special ID card (smart card) or other user identification for activating the special machine, and a special copying machine at the receiving end. At the sender's station, the original document and ID card are inserted into the machine. The latter digitizes the document text, to produce a digital signature which incorporates unique information from the sender's ID card. This machine then produces a hard copy of the document to which is added the digital signature. The sender retains the original, but forwards the copy to the recipient or receiver. The receiver then inserts the received copy into the machine at his location, which digitizes and processes the document text and signature and indicates whether the digital signature is valid. Preferably a dual key authentication system is used, with the digital signature incorporating the sender's secret signing key, and the receiver using the related public key in the validation process.
First Claim
Family
- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
| Patent Owner | Address | |
|---|---|---|
| XEROX CORPORATION | 201 MERRITT 7 P O BOX 4505 NORWALK CT 06851-1056 |
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Bloomberg, Dan S | Palo Alto, CA | 61 | 4687 |
| Brown, John S | San Francisco, CA | 13 | 473 |
| Merkle, Ralph C | Sunnyvale, CA | 43 | 4191 |
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Maintenance Fees
| Fee | Large entity fee | small entity fee | micro entity fee | due date |
|---|
| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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