Validity of the right of the creditor to unilaterally amend the interest rates and fees in relation to long term loan contracts has been challenged in the past few years in Hungary. The Hungarian Supreme Court in a recent uniformity decision ruled that contractual clauses enabling unilateral amendment of a contract are fair if they clearly and intelligibly define how and to what extent changes in the circumstances of causes affect the consumer’s payment obligations. Based on the uniformity decision, the Parliament adopted a new law on the implementation of the decision. The law presumes that all contractual clauses enabling unilateral amendment of a contract are unfair, and the financial institutions have the right to rebut the presumption. The significance of the claims are enormous, as the law covers all consumer loan contracts concluded between 2004 and 2014, which provides unilateral right to the creditor to amend the contract. Gárdos Füredi Mosonyi Tomori represents two major international banks and an international financial lease company in the lawsuits.