Jenneke Schlichte Bergen, Zynyo
Want to enhance your business processes, eliminate paper handling and relieve your co‑workers and customers of administrative burden? Integrate the Digital Signatures API into your own software and sign documents easily, electronically and in accordance with European legislation.

Test Digital Signatures API for free 

About the Digital Signatures API

Like every organization, your organization likely has all kinds of documents that require a signature. With Zynyo’s Digital Signatures API you can digitize this process in a legally valid and reliable way. The API provides full functionality for the electronic signing of documents. It facilitates different roles (like sender, signee, bulk-signee, approver and receiver) and provides status updates during the process (like document received, reviewed, signed). 

Secure signing

Zynyo’s API is made in accordance with Dutch and European legislation (eIDAS) at all desired levels: simple, advanced (AES) and qualified (QES). Their services are hosted in the Netherlands, in a secured data center environment owned by a private company. Zynyo has a private cloud for their services. Only pre-registered persons have physical access to the data center and remote access is restricted to limited roles in the organization. This process has been audited and rewarded with the ISO270001 certificate.

"Like every organization, your organization likely has all kinds of documents that require a signature. With Zynyo’s Digital Signatures API you can digitize this process in a legally valid and reliable way."

How does it work?

With Zynyo’s Digital Signatures API you can manage the complete document signing process. You can, for example, get the current open document sign requests, send a reminder, cancel a document or get the signed document content after completion. You can get updates of the whole process through e-mail, but it’s also possible to automate this process with the use of the callback functionality. The callback functionality will then notify your service when a step in the process has been taken.  

These are the 8 steps a document would go through with the Digital Signatures API:


  1. The signing process starts within your own software application by selecting the document for signing. 
  2. Insert the signees, e-mail addresses and the required method for authentication. Receivers can also be specified in this sign request; they only receive the signed document by e-mail. There is also an API endpoint available to receive the signed document content, if you have the corresponding API key.
  3. The document is submitted to the Zynyo signing service. 
  4. The signee then receives a signing request via e-mail. 
  5. The signee can view the document.  
  6. He or she can sign/validate the document with the chosen means of authentication, or reject the document. 
  7. The transaction information of the signees is given back to the signing service of Zynyo. 
  8. When all signees have signed, the document is extended with an audit log, sealed with a timestamp and a PKI (Public Key Infrastructure) certificate. All signatories receive the signed document via e-mail. Your connected applications can also get a copy with an API call, for which an API-key and the document unique identifier (UUID) are required. 

"The Zynyo process has been audited and rewarded with the ISO270001 certificate for information security."

Benefits of the API 

Plenty of choice from authentication tools

Signing is possible with all common means. For example the so-called mouse signature, SMS-TAN, DigiD, iDIN, or PKI certificates.

Automatic follow-up

Signatories can automatically receive an e-mail or SMS with a reminder if the document is not signed within time.

Bulk signing

Signatories who have to sign multiple documents have the option to sign them as a batch.

Clear backoffice

You get access to the Zynyo Dashboard, which contains all relevant information, including the status of the documents that have been submitted for signing. It’s also possible to see the status of each individual signatory here. The dashboard is available for multiple users; the domain admin can add and invite more users. You do not need an account just to sign a document. 

Audit trail included

All documents are provided with a certified timestamp, an electronic seal with a PKI certificate and an identical (hash) code so that they are easy to archive. With the API, you can also query the status of an open sign request, which returns the document with the state and the document IDs. With the document ID, you can query a detailed state to monitor the individual signatory process.

Internal approval

Let an approver accept or reject a document first, before the document is sent to be signed by the other parties.

Handy templates

Zynyo provides templates where the signatory still has to fill in certain fields and/or check a box.

Initial on all pages

It’s possible to place an initial on all pages of the document. You can even choose to place an initial with one action on all pages of the document.

Prevent fraud with 'quicksign'

This is also called ‘electronic sealing’. When you seal a document with an electronic seal, the document can no longer be modified by the recipient and the recipient has certainty about the identity of the sender. 

Long term validation

Zynyo secures the highest level for long term validation, thereby securing that signed documents can safely be archived. Zynyo supports both PAdES B-LT and PAdES B-LTA signature profiles. Zynyo does not archive documents to minimize the impact on data security breaches. Therefore, you have full control over your own archive. Ultimately a document stays with Zynyo for 30 days. On the 30th day, the document gets the ‘expired’ state and is deleted overnight. If you want to delete a document (signed or unsigned) yourself, you can cancel the document. It will then be expired and deleted. 

"All documents are provided with a certified timestamp, an electronic seal with a PKI certificate and an identical code."

Satisfied customers

At Optimix, a private wealth management bank, the closing of the various different contracts and agreements took a lot of time because of the required multiple signatures from different parties. Due to the implementation of Zynyo, these work processes have been optimized and digitized, which has resulted in much faster handling and more satisfied customers.

The Province of Noord-Holland also benefits significantly from Zynyo's solution:

“Due to Zynyo's Digital Signatures API, the physical signing of contracts is now obsolete, which saves time and administrative workload. Zynyo also tackles the implementation of the digital signature structurally.”

About Zynyo

Zynyo strives for the highest form of quality, security and legal validity in digital signing. They offer a high-end signing service platform and work together with global partners that are specialized in online identity and privacy. This way, Zynyo facilitates legally valid, secured and user-friendly digital signing of all kind documents.

Test for free

Curious about the Digital Signatures API, but would like to try it first? Our cooperation with Zynyo makes it possible to test the API for free in our sandbox environment. The sandbox version covers all basic signing functionalities (like signing a document with SMS-TAN). Through the use of sample data, you can see exactly how the API would function in your own application. 

Test Digital Signatures API for free