GDPdU Explanations

The GDPdU contained the state of the principles for data access / verifiability of the digital documents until 2015 and were replaced by the GoBD. The GDPdU was an administrative instruction of the financial administration (BMF) from 2001 and dealt with the examination of tax-relevant processes.


According to GRADINMATH, the GoBD (= principles for the proper management and storage of books, records and documents in electronic form as well as for data access) apply to every self-employed person and entrepreneur. Anyone who does not adhere to the principles must expect additional claims from the tax office and is liable to prosecution.

The content of the GDPdU

In addition to the obligation to keep digital documents, the GDPdU also regulates the taxpayers’ obligation to cooperate in a tax audit by the tax authorities (BMF). This administrative instruction was issued by the Federal Ministry of Finance and includes the legal norms of the Value Added Tax Act and the Tax Code. In the GDPdU the digital storage of booking documents, bookkeeping and invoices and the use of software systems is specified. The requirements for company audits in the GDPdU are described as follows:

  • The invoice recipients check invoices for completeness of the legally required information and for their formal and factual correctness.
  • The invoices are saved in an unchangeable form.
  • The storage and conversion of the invoice is logged.
  • The invoice recipient is responsible for archiving according to BoBS – principles of a proper EDP bookkeeping system.

The implementation of a tax audit according to GDPdU

When accessing the taxpayer’s data, the tax auditor can choose between direct read access, indirect access via evaluations and data storage media from different formats. The tax auditor may not transfer his own digital software to the taxpayer’s internal system. According to the recommendation of the BMF, different formats can be selected for the transfer of material on data carriers, which can be read into the auditor’s software. If these rules are adhered to, digital documents may also be transferred or outsourced abroad. Compliance with the tax code of the GDPdU has been mandatory since 2008, and violations can result in a fine of between 2,500 and 250,000 euros.

The data formats of the GDPdU

The IDEA software is used by the tax auditors and recognizes the following data formats if the structural information is available in an evaluable form:

  • Fixed length ASCII
  • ASCII Delimited (including comma-separated value)
  • Excel
  • Lotus 123
  • ASCII print files with information for data elements and structure
  • Files from SAP / AIS
  • Fixed-length EBCDIC files
  • EBCDIC variable length files
  • Access
  • dBASE

It is also possible to convert AS / 400 data record descriptions into RDE data record descriptions – these are FDF files that were created by PC-Support / 400. Furthermore, the import via an ODBC interface is also possible. If information is available that is saved in different file formats, then this must be converted.

The process documentation according to GDPdU and GoBS

The GoBS (principles of proper IT-based accounting systems) is a provision from 1995 and, together with the HGB, forms the basis for the procedural documentation. The GDPdU is based on the GoBS. The process documentation is useful as evidence and also serves to ensure the transparency of compliance with all legal requirements and requirements. They describe the course of the billing process between creation and retrieval of the data. Within the process documentation, logical and technical solutions must be described as well as the preservation of the program identity and the data integrity. Last but not least, work instructions for using and archiving the program are also required.

Which contents are regulated in the GDPdU?

  • Type and scope of access to tax-relevant digitized data.
  • The duty of the taxpayer to cooperate in a tax audit
  • The storage and archiving of the documents

The term “tax-relevant data”: This is not generally regulated for all tax audits with regard to the principles of data access and the verifiability of digital documents. This arises for the reason that these always result from the circumstances of the individual case, whether certain information shows a tax significance and this includes information that may be of importance when it comes to the taxation of the company.

Which data carriers are accepted by the tax authorities?

  • CD-ROMs
  • DVDs in ISO standard
  • Floppy disks that use the FAT or MS-DOS file systems

The retention periods for the business documents

The taxpayer must always adhere to the retention periods for business documents. A 10-year retention period applies to all records – including balance sheets and other annual financial statements – and the organizational documents and work instructions required for their understanding, as well as the accounting documents. For example, a six-year retention period is required for originals and copies of business letters.

The ERP system facilitates the obligation to cooperate.

An ERP system can support smaller taxpayers, freelancers and the self-employed in fulfilling the obligation to cooperate in the context of a tax audit. This system helps avoid violations that can result in significant financial penalties. An ERP system that is tailored to smaller companies maps all business processes in an integrated form and ensures that the database is always up-to-date and coherent, which ensures that a smooth tax audit can be carried out.