Тhe purpose of this article is to assess the authority of the bankruptcy Trustee (Deposit Insurance Agency) to challenge the transactions of a debtor – a credit institution that is in bankruptcy. Current legislation and practice provide a basis for discussion as to whether such power is the bounden duty of the bankruptcy trustee, or the administrator has the ability to waive the claim. The authors examine the features of the bankruptcy trustee's legal position, the current judicial practice and make a clear conclusion: in accordance with the current legislation, including taking into account the meaning given to it by the legal positions of the courts, challenging the debtor's transactions is the duty of the bankruptcy trustee. This conclusion, in particular, arises from the fact that the Deposit Insurance Agency performs the functions of a bankruptcy trustee by law and is obliged to protect public interests. When making a decision to appeal transactions, the bankruptcy trustee must act in good faith and reasonably, comparing the economic effect of invalidating the transaction with the costs of challenging it. There is a need to improve the legal position of the Deposit Insurance Agency in terms of performing its functions as a bankruptcy trustee of credit organizations.