Companies can't borrow money from each other, and the main contract of borrowing money is invalid, so the mortgage as a subsidiary contract can't be established, and the real estate intermediary agency will not register the mortgage; Inter-enterprise borrowing refers to the civil act of borrowing funds from each other between two enterprises without financial management rights. Regarding the validity of the enterprise loan contract, the second paragraph of Article 11 of the Commercial Banking Law clearly stipulates that no unit or individual may engage in commercial banking business such as absorbing public deposits without the approval of the banking regulatory agency; Money lending is a kind of financial business, and its stability is related to the long-term stability of a country's economy. It can only be monopolized by financial institutions designated by the state, while lending between non-financial institutions has always been prohibited by the laws of China. For a long time, the judicial practice has always held a negative attitude towards the effectiveness of inter-enterprise loan contracts, that is, they think that inter-enterprise loan contracts are illegal and should be invalid. On the treatment of enterprise loan interest. According to the judicial interpretation issued by the Supreme People's Court, the borrower will only return the principal, not the interest, in the case of handling illegal lending disputes between enterprises. Moreover, from the date of repayment agreed in the contract to the time when the judgment determines that the borrower will return the principal, the interest that the parties have obtained or the interest that has been agreed but not yet obtained shall be fully recovered.