PKO vice president Rafał Kozłowski announced the introduction of an electronic regulation document delivery system. - The bank acquired the ability to send correspondence to its customers using blockchain technology - Kozłowski said. He added that the next correspondence about changes in the bank's offer will be distributed using the new solution. It will be sent out in September and will concern changes in regulations following the implementation of the PSD II directive.

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PKO BP's announcement means that the bank might become the first one in Poland to use blockchain technology to create a durable medium. Several other institutions decided to use the WORM matrix (a storage server that guarantees the unchangeability of files saved on it). They include banks such as BZ WBK and Pekao which work with Hitachi to provide the service.

The question of durable mediums became a problem in Poland several years ago when it became the Office of Competition and Consumer Protection's concern. The anti-monopoly regulator emphasizes that banks should send information to their customers in a way that prevents from making one-sided changes to it. A durable medium is also supposed to give customers access to documents even after their contract with the bank is no longer in force.

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In the past the Office of Competition and Consumer Protection (UOKiK) initiated proceedings against several banks that used to send information about changes in rates or regulations to their customers via their electronic banking systems. According to the regulator, this correspondence method doesn't always constitute a durable medium. Some of those proceedings, including the one against PKO BP, are still open. The bank set aside an amount of approximately 60 million złoty (14 million euro) for possible costs related to the proceedings.