Several standard provisions of bank regulations on rules of determining conversion rates of currencies have been found to be unfair terms.
https://decyzje.uokik.gov.pl/bp/dec_prez.nsf/43104c28a7a1be23c1257eac006d8dd4/9cee9ee78472077dc12585ec00283db7/$FILE/WERSJA%20JAWNA_20200922_decyzja%20Santander_BIP.pdf