The traditional function of a signature is to permanently affix to a document a person's uniquely personal, undeniable self-identification as physical evidence of that person's personal witness and certification of the content

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The signature on a painting or other work of art has always been an important item in the assessment of art. Fake signatures are sometimes added to enhance the value of a painting, or are added to a fake painting to support its authenticity. A notorious case was the

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Under British law, the appearance of signatures (not the names themselves) may be protected under copyright law.
Under United States copyright law, "titles, names [I c...]; mere

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• Autograph club
• Autograph Collector Magazine
• Biometric signature as form of the electronic signature

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• Why Do We Sign For Things? A Rabbi, A Lawyer And A MasterCard Exec Explain NPR / Planet Money
• History of signatures at Slate
• What is Signature? Signature of 100 famous people

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Uniform Commercial Code §1-201(37) of the United States generally defines signed as "using any symbol executed or adopted with present intention to adopt or accept a writing." The Uniform Commercial Code §3-401(b) for negotiable instrumentsstates "A signature may be made

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