Electronic signatures
First Claim
1. A method comprising:
- receiving a signed electronic document comprising an electronic document and a signature document, the signature document including an electronic handwritten signature applied to first image and a digital watermark, wherein the digital watermark is a second image representing a watermark that overlays at least a portion of the first image and embeds in the signature document a first one-way hash calculated using the electronic document, and where the applied electronic signature altered an appearance of the signature document;
verifying an integrity of the digital watermark based, at least in part, on an integrity of the electronic handwritten signature applied to the image;
obtaining the first one-way hash from the first image in connection with at least determining the integrity of the digital watermark;
calculating a second one-way hash for the electronic document;
comparing the first one-way hash to the second one-way hash; and
verifying by a receiving device contents of the signed electronic document based at least in part on the one-way hash comparison.
2 Assignments
0 Petitions
Accused Products
Abstract
Methods, apparatus, including computer program products, and systems implement and use techniques relating to electronic signatures. In one implementation, a one-way hash is calculated for an electronic document and a digital watermark representing the one-way hash is embedded in a signature document. Based on a user input, the signature document having the embedded digital watermark is altered, and the electronic document is associated with the signature document. The electronic document and the signature document together comprise a signed electronic document. The user input can include biometric information, such as a handwritten signature or a voice recording. For additional security, the one-way hash can be encrypted before a representation of the hash is embedded in the signature document.
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Citations
33 Claims
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1. A method comprising:
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receiving a signed electronic document comprising an electronic document and a signature document, the signature document including an electronic handwritten signature applied to first image and a digital watermark, wherein the digital watermark is a second image representing a watermark that overlays at least a portion of the first image and embeds in the signature document a first one-way hash calculated using the electronic document, and where the applied electronic signature altered an appearance of the signature document; verifying an integrity of the digital watermark based, at least in part, on an integrity of the electronic handwritten signature applied to the image; obtaining the first one-way hash from the first image in connection with at least determining the integrity of the digital watermark; calculating a second one-way hash for the electronic document; comparing the first one-way hash to the second one-way hash; and verifying by a receiving device contents of the signed electronic document based at least in part on the one-way hash comparison. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A system comprising:
one or more processors configured to; receive a signed electronic document comprising an electronic document and a signature document, the signature document including an electronic handwritten signature applied to first image and a digital watermark, wherein the digital watermark is a second image representing a watermark that overlays at least a portion of the first image and embeds in the signature document a first one-way hash calculated using the electronic document, and where the applied electronic signature altered an appearance of the signature document; verify an integrity of the digital watermark based, at least in part, on an integrity of the electronic handwritten signature applied to the image; obtain the first one-way hash from the image in connection with at least determining the integrity of the digital watermark; calculate a second one-way hash for the electronic document; compare the first one-way hash to the second one-way hash; and verify contents of the signed electronic document based at least in part on the one-way hash comparison. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
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19. A method comprising:
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receiving a signed electronic document comprising an electronic document and an audio signature file, the audio signature file including a voice recording applied to a first audio recording and a digital watermark, wherein the digital watermark is a second audio recording representing a watermark that overlays at least a portion of the first audio recording and embeds in the audio signature file a first one-way has calculated using the electronic document, and where the applied electronic signature altered the audio signature file; verify an integrity of the digital watermark based, at least in part, on an integrity of the voice recording applied to the first audio recording; obtaining the first one-way hash from the second audio recording in connection with at least determining the integrity of the digital watermark; calculating a second one-way hash for the electronic document; comparing the first one-way hash to the second one-way hash; and verifying by a receiving device contents of the signed electronic document based at least in part on the one-way hash comparison. - View Dependent Claims (20, 21)
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22. An apparatus comprising a computer-readable medium storing instructions operable to cause a programmable processor to:
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receive a signed electronic document comprising an electronic document and an audio signature file, the audio signature file including a voice recording applied to a first audio recording and a digital watermark, wherein the digital watermark is a second audio recording representing a watermark that overlays at least a portion of the first audio recording and embeds in the audio signature file a first one-way has calculated using the electronic document, and where the applied electronic signature altered the audio signature file; verify an integrity of the digital watermark based, at least in part, on an integrity of the voice recording applied to the first audio recording; obtain the first one-way hash from the second audio recording in connection with least determining the integrity of the digital watermark; calculate a second one-way hash for the electronic document; compare the first one-way hash to the second one-way hash; and verify by a receiving device contents of the signed electronic document based at least in part on the one-way hash comparison. - View Dependent Claims (23, 24, 25, 26, 27, 28, 29, 30)
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31. An apparatus comprising a computer-readable medium storing instructions operable to cause a programmable processor to:
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receiving a signed electronic document comprising an electronic document and an audio signature file, the audio signature file including a voice recording applied to a first audio recording and a digital watermark, wherein the digital watermark is a second audio recording representing a watermark that overlays at least a portion of the first audio recording and embeds in the audio signature file a first one-way has calculated using the electronic document, and where the applied electronic signature altered the audio signature file; verify an integrity of the digital watermark based, at least in part, on an integrity of the voice recording applied to the first audio recording; obtaining the first one-way hash from the second audio recording in connection with at least determining the integrity of the digital watermark; calculating a second one-way hash for the electronic document; comparing the first one-way hash to the second one-way hash; and verifying by a receiving device contents of the signed electronic document based at least in part on the one-way hash comparison. - View Dependent Claims (32, 33)
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Specification