• Integrity

    Switch from paper to an electronic format and enhance security within your PDF documents. Add digital signatures to ensure your documents are secure. Encrypted digital signatures secure PDF documents–making them difficult to reproduce or forge.

  • Multiple Signatures

    Incrementally update PDF documents and validate digital signatures with multiple signatures. Signature for the .NET API library allows you to add various types of signatures to supported file formats. Adjust the signature properties and appearance as needed.

  • Authenticity

    Ensure non-repudiation, verify and authenticate an author's signature. Allow users to prover authorship or the validity of a contract or document.

  • Certificates

    Apply digital certificates to a PDF file with a signature line and retrieve additional information from the signature's binary data. When a document is signed using a certificate, the updated signed PDF is saved with the original PDF as append-only, and the original cannot be modified.

  • Validity

    Timestamp and validate signatures of existing PDF documents. Timestamps are essential for keeping records of when information is exchanged, created, or deleted online. Validate a signature to prove the authenticity of the signature timestamp.

  • Customize

    Fully customize the appearance of the digital signature. Apply background color, borders, captions, customize caption location, and full-text support on the signatures. Add text, graphics, images, or shapes to a digital signature. Specify the signer and location for a pop-up and field lock options for signatures.



Digital timestamps mark a PDF signature with the time and date as proof of integrity. A timestamp shows that the contents of the document existed at a point in time and are unchanged.

  • Authentication and validation of document integrity
  • Establish copyright protections
  • Proof of intellectual property rights for patents

Extract Certificate Details

Extract Certificate Details

Extract signature information to troubleshoot problems that may occur due to binding dates of the certificate.

  • Confirm that a certificate meets security requirements
  • Validate key usage and timestamp authority
  • Enforce particular security requirements (e.g. valid public key digital signature with valid timestamp server)

Long-Term Validation Signatures

Long-Term Validation Signatures

Add long-term validation enabled signatures to your documents. Certify a document to ensure that a signature is valid at the time of signing. Compliant with Cryptographic Message Syntax (CMS), the advanced format of the Public Key Infrastructure (PKI)

  • Allows for multiple signatures
  • Create custom approval workflows
  • Certify with timestamps and encryption

Visual Signatures

Visual Signatures

Add an image to represent the signature with minimum lines of code. Add signature captions relative to the image. Supports JPEG, PNG, BMP, TIFF, GIF, and EXIF images. Customize image resolutions and the EXIF profile of images or signatures.

  • Create your own customized signature to look like your own
  • Reuse your custom signature across documents
  • Hover over a signature to get details about the signer and location

Documents Media