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.NET PDF Signature Library

Use digital signatures and certificates to ensure the authenticity and integrity of your PDF documents.

Add advanced signing support with a high level of security to all your applications with the GdPicture.NET PDF Signature SDK, including:

PDF/A compliance

Various digital certificates support

Timestamp support

Multiple signatures support

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Illustration GdPicture.NET PDF Signature SDK

Digital signatures

Each country has laws regarding the use of digital or electronic signatures.
In the European Union, the eIDAS regulation allows three types of electronic signatures:

the simple electronic signature suitable for everyday acts or those with low legal or financial consequences for the signatory.
the advanced electronic signature, which includes the use of a digital certificate.
the qualified electronic signature, generally used for authentic acts of notaries, lawyers, bailiffs, courts, and the like. Its security criteria are comparable to those of the advanced digital signature.

Still, its procedure cannot be entirely carried out remotely: a certification authority approved by the government must verify and validate the identity of the signatory.

You can use the GdPicture.NET PDF Signature SDK in all cases, thanks to the high level of security and the ability to import a digital certificate.

Main features

PDF/A conformant signatures
Support for European Signature Standards
Add an optional visual appearance of the signature (page, size, color, position, text, image, etc.)

Support for Multiple Signatures
Remove digital signatures

Illustration Digital certificates

Digital certificates

A digital signature certificate (DSC) contains information about the user’s name, pin code, country, email address, date of issuance of the certificate, and name of the certifying authority. It also makes it possible to prove that the document has not been modified since the signature. The digital certificate is an electronic file, as well as a private key allowing cryptographic signature operations. Only a Certification Authority, whose role is to verify the identity and make the link between the private signature key and the identity of the signatory, can issue a certificate.

Main features

Certify documents using Modification detection & prevention (MDP)
Apply signatures using:
Public Key Cryptography Standard #12 containers (pfx, p12)
Windows certificate store
Smart Cards

Security of the digital signing process

The digital signature process is based on an encryption system with a private key (which is used to sign) and a public key (to verify the signature). It is this encryption system that allows authentication of the document sender. To ensure the highest security level, GdPicture.NET uses the SHA-256 hash algorithm.
Read more about the safety of the signing process.