Authentic
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Certify your PDFs haven't changed since we sealed them for you - without leaving Acrobat
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Leverage PDF’s built-in capability to prove your documents are authentic
When Adobe created the Portable Document Format (PDF), they included the ability to Seal a document. It’s a way to mathematically prove that a PDF hasn’t changed since the seal was applied. This is the technology that services like DocuSign and Adobe eSigning Solutions use to prove a document hasn’t been altered after the seal is applied. This protects signatures in agreements and contracts. It can protect pdf reports provided by a company or a department with a legally valid distinction between legitimate and fraudulant reports.
Understanding PDF Sealing & Verification
Digital sealing (also called digital signing) proves two important things about your PDF documents:
- Authenticity: Confirms who (an individual or a company) signed the document.
- Integrity: Ensures the document hasn’t been changed after signing.
How PDF Sealing Works
Step 1: Creating a Digital Fingerprint
Every PDF has a unique digital fingerprint—called a hash—created by applying a special mathematical function. If even one small detail of the document changes, the fingerprint changes completely.
Step 2: Signing the Fingerprint
Trusted Signers uses a secure digital key (similar to a secret stamp) to “seal” this fingerprint. This creates a secure certificate known as a digital signature.
Step 3: Embedding the Signature
This digital signature is then securely embedded into the PDF. The document is now “sealed”.
How PDF Verification Works
When someone opens your digitally sealed PDF:
- The PDF viewer software (like Adobe Acrobat) examines the embedded signature.
- It compares the current document’s fingerprint with the fingerprint in the signature.
- If they match exactly, the viewer confirms that:
- The PDF is authentic.
- It was signed by the indicated signer.
- Nothing has changed since it was sealed.
If anything has been altered, the verification fails, clearly alerting the reader.
Why is Digital Sealing Important?
- Trust: Anyone viewing the document knows it’s authentic and unchanged.
- Security: Prevents forgery, tampering, and backdating.
- Compliance: Accepted by courts, auditors, and regulatory authorities worldwide.
Trusted Signers makes this process simple, secure, and accessible.
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