A digital signature is a mathematical process that allows to demonstrate the authenticity of a digital message or document. A valid digital signature allows the recipient to identify the sender of the message, in a way the sender can not deny having sent the message. It is also possible to verify that the message was not modified during transit.

In a digital signature it is possible to verify when it occurred (timestamp), if there were changes to the document after it was signed and check the signer's identity. Also, it is impossible for a signer to deny having signed the document. With manual signature it is not possible to verify this infallibly.

Yes, a document management process that uses digital signature will effectively reduce costs. Printing and scanning as well as manually signing each page of the document is no longer necessary. It also prevents costs for mandatory physical documents exchange as well as notarized recognition of signatures.

The user may sign any document, since it is in PDF format.
Examples of application areas:

> Agreements
> Commercial proposals & public procurement
> Official documents

Yes, a digital signature made ​​with Assinare using a Citizen Card is legally recognized without an authentication by a notary.

Yes, as long public procurement platforms accept digital signing through specific signature certificates under current legislation. In Portugal for instance digitally signing a document with the Portuguese Citizen's Card certificate is qualified and valid under public procurement platforms.

No, any modification to a document previously signed will invalidate all the existing digital signatures. Therefore, it is possible to check if a document has been changed after being signed and thus determine its integrity. This is not possible with conventional manual signing.

Yes, using a program to open PDF documents that have this functionality. Such as Acrobat Reader.
(see "how to check other signatures in a document")

Countries where the law currently addresses validation of digital signatures include: Argentina, Bermuda, Brazil, Canada, China, Colombia, European Union, Ghana, Guatemala, India, Japan, Korea, Malaysia, Moldavia, New Zealand, Peru, Philippines , Russia, South Africa, Switzerland, United States, Uruguay, Turkey. It is expected that in the near future recognition of the digital signature will expand worldwide.

In order to make a digital signature using Assinare, it is necessary that a user has a smart card with digital signature enabled and the appropriate PIN code; a card reader and a computer with internet connection. Note that it is not necessary to install specific software for the card reader.

No. Assinare can be used in any computer just by connecting the card reader to it. No software needs to be installed and no new certificates need to be acquired.

In order to have the document signed by different people:
1. First user signs the document
2. First user save and closes the document
3. Second user repeats the process. And so forth.

In order to check if a document has already been digitally signed and what is the information for a signature:

1. In the lower right corner of the preview panel there should be a green closed lock in case the document is signed. Otherwise a grey open lock will be shown.

If document already has signatures, the number of signatures will be indicated next to the green lock. Clicking this number will show information on the signer(s).

2. By opening the PDF file with the Adobe Reader program you will be able to consult existing signatures:

On the document, where it has been signed. View the signers' full name, date, hour, location, reasons and additional information. By clicking with the right button on a signature it's possible to validate it and view it's properties.

On the signature's list. By clicking on each item on the list you'll be redirected to the signature's location on the document. It's possible to verify on this list if the document has been altered, the validity of the signature with the associated certificate and the timestamp accreditation. To access this list use:view > navigation panels > signatures

In order to select the type of signature you desire select on the selection bar under "SIGNATURE OPTIONS"

1. On the application, under "SIGNATURE OPTIONS", select "Customized"

2. Click on the magnifying glass icon to select the desired image

3. Sign

Yes. When you're using a card reader with no keypad, Assinare allows you to select different documents and signing them by entering your PIN number only once.