dBridge – blockchain solutions

Durable Medium

by dBridge.

based on blockchain

Durable Medium (DM) guarantees safe access to documents with integrity and immutability of records.

Compliant with requirements of

What is Durable Medium


It is a legal concept introduced by the European Union in 2017. It requires financial institutions to provide their clients with documents using a durable information medium, which guarantees the invariability of records and access to them also after the end of the client’s cooperation with a given institution. The most popular by now and very expensive are: paper, CD/DVD, pendrive, WORM matrix.

The functionality of our Platform allows replacing the traditional mass mailing to your customers by providing access to the content of transferred information. It meets the legal requirements of banks, investment funds, and other financial institutions. Their customer gains access to the information stored in the file through the distribution system (e.g. STI 24) or a link provided by SMS or e-mail.

The files are placed on a specially prepared DM Platform that provides:

  • permanent saving of information intended for the customer without the possibility of modification, deletion or concealment

  • zero possibility of invisible deletion/withdrawal of access to information designed for the customer by both the fund and the customer – for the period required by law

  • access to information designed for the customer also when his agreement has expired.

Who is obliged to use DM under EU law ?

tour operators
pension funds
real estate developers
e-commerce operators
issuers of the securities
payment service providers
investment firms and advisors
crowdfunding service providers
creditor or consumer credit brokers
telecommunications service providers
entrepreneurs concluding any distance contract with a consumer
The most important acts of EU law, relating to DM:
  • Directive (EU) 2019/2161 of the European Parliament and of the Council of 27 November 2019 amending Council Directive 93/13/EEC and Directives 98/6/EC, 2005/29/EC and 2011/83/EU of the European Parliament and of the Council as regards the better enforcement and modernisation of Union consumer protection rules.
  • Directive (EU) 2011/83/EU of the European Parliament and of the Council on consumer rights, amending Council Directive 93/13/EEC and Directive 1999/44/EC of the European Parliament and of the Council and repealing Council Directive 85/577/EEC and Directive 97/7/EC of the European Parliament and of the Council
  • Regulation (EU) 1286/2014 of the European Parliament and of the Council of 26 November 2014 on key information documents for packaged retail and insurance-based investment products (PRIIPs)
  • Directive (EU) 2015/2366 of the European Parliament and of the Council of 25 November 2015 on payment services in the internal market, amending Directives 2002/65/EC, 2009/110/EC and 2013/36/EU and Regulation (EU) No 1093/2010, and repealing Directive 2007/64/EC
  • Directive 2008/48/EC of the European Parliament and of the Council of 23 April 2008 on credit agreements for consumers and repealing Council Directive 87/102/EEC
  • Directive (EU) 2015/2302 of the European Parliament and of the Council of 25 November 2015 on package travel and linked travel arrangements, amending Regulation (EC) No 2006/2004 and Directive 2011/83/EU of the European Parliament and of the Council and repealing Council Directive 90/314/EEC

Durable Medium

by dBridge

Access to documents on a Durable Medium based on blockchain is available on dBridge Platform. The solution guarantees the integrity, security and non-repudiation of the information stored in the documents stored in a cloud. The document published on our platform is divided into encrypted fragments, of a fixed size, and then these

fragments are separately recorded in transactions on distributed registers. Submitting the original document as a whole requires downloading information and relevant fragments from the Platform, which can only be done by the institution and the client of this institution.


document on a platform

Sending a notification

with decoding keys to the client

(e-mail, text, push notification in the mobile app)

Collecting decoding keys

by the client

Downloading a document

by the Platform client using the link and codes

If the client loses the links to documents, it is possible to log in on the Platform.

If a contract with the client is terminated, the user will be able to use the portal of historical data,
which will always be working, regardless of whether the source system that powers the Platform with documents is working.

Key advantages

  • Cost reduction

    related to the reduction ofprinting/copying/shipping

  • CO2 emission reduction

  • Ease of installation

    as the system can be built on any computing cloud. No need of WORM

  • The system is a peer-to-peer network

    in the cloud(s) around the world, with quick access to datafrom the local network

  • GUI for customers

    to access their private data

What do you gain with Durable Medium


  • Cryptographically guaranteed features

  • Service of private (e.g. a contract) and public documents (e.g. regulations, fee charts).

  • Zero chances to modify the documents in the system

  • Zero chances to remove documents from the system

  • Life access to documents

  • Ability to share a link to the chosen document(s)

  • Access to documents through the Portal and mobile application

  • Ability to add documents by clients of our Customers

  • A unique access code to the document (UAK/CID/content address).

  • Storage of any file type: PDF, audio/video, accounting documents, transaction logs, CDR, etc.

  • Coding “in transit” and “at rest” data according to KNF recommendations

  • Compatibility with GDPR

  • Access to documents 24/7

  • Electronic signature consistent with eIDAS

Why is it worth using the Durable Medium by dBridge


  • Full compliance with regulations

  • Low cost of implementation and maintenance (TCO) comparing to our competitors solutions

  • Easy implementation with ability to integrate with the existing systems through API and micro-services

  • Bespoke solution with client’s needs

How to implement our solution


Our DM Platform has all the features of a durable medium such as WORM matrix, but at the same time guarantees much lower costs of implementation and maintenance. Also – contrary to the WORM matrix – it ensures the lack of possibility to remove documents, and provides multi-node clusters of efficiency and reliability, as well as the high level of re-duplication of the document content.

The platform is implemented in two models

Bespoke in the cloud or on-premises

The solution is usually tailored to our Client’s needs: dBridge implements the Platform on the existed IT environment which finally manages the Platform. The Client should also provide the correct interfaces for transferring documents to/from the Platform.


dBridge ensures access to the Platform in the Managed Services model, using our own data processing centre. We ensure access to documents also after the expiration of of the contract. The Client needs to ensure the proper interfaces for transferring documents to/from the Platform. It is also possible to share Client’s documents through the Client’s platform (e.g. online banking) via API to our Platform.

Business models

  • SaaS for SMEs (per each page of a document or bulk of documentsor per GB storage)

  • Bespoke solution for enterprises (per user and per GB storage)

  • On premise for enterprises