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(Author: A-SIT^(?))

A service for uploading and adding signatures to PDF files in a web browser.

Available for:

(Author: A-SIT^(?), powered by RTR^(?))

Available for:

Free Software for PDF Signatures

PDF-OVER for smartcard^(?) and mobile phone signature^(?)

Version 3.2.5, Feb. 2, 2012

(Author: A-SIT^(?), A-SIT Terms of Use)

Available for:

Downloads:

(approx. 25 MB, depending on the operating system)

Windows : Installer

MacOS : zipped dmg German, English

Linux : ZIP file German, English

Documentation:

Brief overview (for all operating systems)

Screenshots of the application

Changes to previous version

Also see PDF-AS and application notes

PDF and E-Mail Signatures

The citizen card allows you to legally sign documents such as contracts, receipts, cancellation notices or forms electronically (in PDF format). These files can then be sent via e-mail. The e-mail can also be signed. However, in comparison to the signed document, it is still relatively unsecure and often not necessary. Detailed information on e-mail signatures

Signing e-mails has three disadvantages:

It is not secure because the subject and other header information is not signed. This means that this information could be manipulated on the way to the recipient.
E-mail signatures are based on RSA^(?) encryption and therefore only works with the e-card G3^(?).
E-mail signatures are not as legally binding. It is only an advanced signature^(?) (not qualified^(?)) because the RSA certificate on the e-card is not a qualified certificate^(?).

If you still would like to sign e-mails:

You can only sign e-mails if your respective e-mail address(es) are entered in the certificate^(?).
- If you already have a citizen card, you can check here to see which e-mail address(es) are saved in your certificate
- If you do not have a citizen card yet, you will need to enter your e-mail address(es) upon activation^(?).
- It is not possible to change your e-mail address in the certificate afterwards. In order to add e-mail addresses, you must first revoke the citizen card and then activate it again. Informationen on revoking your citizen card.
Follow the installation instructions from A-Trust for your e-mail program

It is not currently possible to sign e-mails with the Apple MacOS.

What are signed PDFs good for?

Basically, signed PDFs take the place of anything you usually need to send in the mail whether it's an official form or just plain text. E.g.: Insurance claims, mobile phone cancellation letters, bills, certificates, all types of contracts, notices to public authorities.

Examples

Send electronic bills

Small companies can save time and money. Just download the software offered here, such as PDF-OVER, and start sending bills as signed PDFs.

The recipient is only eligible for a tax deduction if the electronic bill is signed with an advanced signature^(?) (or transmitted via an EDI algorithm). This is covered in the regulations for the requirements for bills transmitted by electronic means .

Note: The recipient must agree to receive bills in electronic form: VAT Law (UStG) § 11. (2): A bill sent electronically is still regarded as a bill, as long as the recipient agrees.

Send cancellation notices or contracts via e-mail

Every company is obligated to accept signed PDFs as a declaration of intent (unless it is explicitly excluded in the company's General Terms and Conditions). Note: Although a signed PDF is "watertight", e-mails can still get lost in transit. Make sure to get a confirmation that the company received your e-mail.

Fill out the PDF form

Unfortunately, most PDF forms can only be filled out using Adobe Reader, and not saved. However, you can do this with e.g. the free Foxit Reader. Save the completed form and sign it. Then just send it by e-mail.

Do I have to accept a signed PDF?

Short answer: Unless not explicitly excluded, yes.

Long answer: A signed PDF is just as "watertight" as a signed document. It is considered a written document. The Signature Act defines the equivalence of a qualified signature and a handwritten signature. Its application can in specific cases be excluded by law (e.g., need for notarization, testaments, ..) or be excluded via party autonomy in formation of contracts (e.g. via terms of business).

How can I verify the signature?

A signature verification check is the only way to make sure that a PDF was really signed. This is even more essential with important documents.
Here's how to verify a signature:

First try it with Adobe Reader (with VPDFSign, hotPDFsign/hotPDFverify, or trustDesk professional installed): Click on the menu Show Navigation Pane > Signatures and then on the Verify All button). Other online alternatives: Signature verification from RTR, Signature verification from A-Trust or Verification service from IT Solution
If the signature is not shown, try online signature verification from RTR .
If still nothing appears, be sure to get into contact with the sender. It could turn out to be a separate PKCS#7 signature. With this type of signature, there will be a separate file with a .p7s extension. In this case, verifying the signature is only possible using special applications.

More information on various PDF signatures

All signature types are based on the PKCS#7 standard. Three different signatures have been developed on the basis of this standard:

Adobe signature: The actual signature is saved in a special invisible area of the PDF file (called the Signature Dictionary in the Incremental Update Block). The signature is displayed in a special signature window in Adobe Reader.
PDF-AS: This signature is saved in a signature block^(?) and is shown normally along with the rest of the document. There is no additional invisible signature area.
Signature in separate .p7s file: The signature is saved in a separate file with the .p7s file extension. The PDF itself does not contain any references to the signature.

Legal Basis

Electronic Signature Act (SigG) § 4 (1) states: A qualified electronic signature^(?) fulfils the legal definition of a written signature, in particular with regards to § 886 of the civil code (ABGB), if no other law prohibits its use or other terms have been agreed to.

Signature Standards

Unfortunately there are two competing standards for signing PDFs. The Adobe signature is used worldwide. An overview of both types:

Adobe Signatures
(see software below)

The specification is developed by Adobe (creator of the PDF format)

Advantages

Signature can be verified directly in Adobe Reader
Signature can be verified online
Qualified electronic signature^(?) as per Austrian Electronic Signature Act (SigG)

Disadvantages

Current standards do not yet support the ECDSA^(?)algorithm, which is used by the citizen card.

Background information

Why do I need a plug-in?
Two reasons:

A-Trust^(?) root certificate^(?) is not integrated into Adobe Acrobat.
Adobe does not support ECDSA^(?) encryption, which is used by the citizen card (i.e. no qualified signature^(?)). That is also the technical reason why the signature can't be integrated into Adobe's Sign Menu.

Adobe signatures are always binary (i.e. the file is signed just the way it is on the hard drive).

Adobe signatures are not shown in the document. They are saved in a Signature Dictionary, which is part of the Incremental Update Block.

Software

a.sign VPDFSign

download (approx. 4 MB, Author: A-Trust^(?))

Function: Stand-alone software for signing PDF documents. It is integrated using a plug-in in Adobe Reader and Adobe Acrobat.

Screenshot:
a.sign VPDFSign

Desktop icon:
a.sign VPDFSign

System requirements:

Windows
a.sign Client^(?)

More information

There is an additional plug-in for signature verification (already integrated in VPDFSign).

The software can sign PDF/A files (but cannot convert PDF to PDF/A).

With the visible signature option, an image can be inserted into the PDF document that strongly resembles the signature block^(?) of the PDF-AS^(?) standard. This image is not a representation of the actual signature; it is just used as a visual cue:

Visible signatures

sPDF

download (approx. 0.4 MB, Author: Langkamp-IT)

Function: A mobile PDF signature solution for Android mobile phones.

Screenshot:
sPDF .

Attention: Security information under "More information".

System requirements:

Android 2.2 or higher

More information

Security of the mobile phone signature depends on users' measures. Security is significantly increased if separate devices are used for receiving the SMS and the viewing / signature process.

BDC hot:PDFSign

download (approx. 10 MB, Author: BDC^(?))

Function: A commericial plug-in for Adobe Acrobat for creating and verifying signatures. It has integrated document analysis and cleaning functions.

Screenshot:
BDC Hotsign .

System requirements:

Microsoft Windows XP, 2000 or Vista
Adobe Acrobat 6.0/7.0/8.0/9.0 (Standard or Professional)
Intel Pentium II or equivalent
10 MB free disk space
256 MB RAM memory
Card reader (list of supported card readers)

More information

hot:PDFSign provides a mechanism for recognising highly-sensitive documents, and if desired remove critical objects such as JavaScript, notes, alternative text, etc.

trustDesk Professional

download (approx. 9 MB, Author: IT Solution^(?))

Function: Commercial software for signing PDF documents and more. It is a stand-alone program that also installs a plug-in in Adobe for verifying PDF documents.

Screenshot:

trustDesk Professional

Desktop icon:

trustDesk Professional icon

System requirements:

Microsoft Windows XP, 2000 or Vista
Intel Pentium III or equivalent
128 MB available memory
card reader (list of supported card readers)

More information

This software must be purchased, but comes with a 30 day test version.

It offers many functions and plug-ins, for example

Detached signatures for all files types
Signatures for PDF documents
En/Decryption
Signature printer

PDF-AS Signatures

This specification is from EGIZ^(?) (AS comes from the German word Amtssignatur^(?), meaning official signature. Now all citizen card users can sign using PDF-AS).