Subsidiary liability when a debtor organization is declared bankrupt is the additional liability of persons who, along with the bankrupt debtor, are liable to creditors for the proper performance of an obligation in cases provided for by law or contract. In other words, if the debtor organization has insufficient assets and financial means to repay obligations to creditors, then persons controlling the debtor organization (founders, management, chief accountant, etc.) may be brought to subsidiary liability.
Article 61.10 of Federal Law No. 127-FZ "On Insolvency (Bankruptcy)" defines a controlling person as a person or organization that imposed actions on the debtor. For example, the person gave binding instructions to conclude transactions.