Limited liability company rented a real estate entrepreneur. In this case the landlord and the tenant signed an agreement to lease the property. The organization actually took the shot from rental real estate. When it was time to pay for the leased real property, the organization began to refuse to pay to lease space. Lessor had to go to arbitration with a claim for recovery of arrears of rent and interest. In the Court of Arbitration Society has adopted the position that the lease contract is not concluded, since the parties signed the lease agreement does not contain information that would determine exactly what specific property is subject to contract. Then at trial the plaintiff until the court decides on the charges against the requirements stated on changing requirements, and demanded to make a decision on the recovery from the organization not rent, but the amount of unjust enrichment, the organization formed by the free use of facilities, said the need for compulsory repayment of debt. Court of First Instance stated requirements have been satisfied in connection with the fact that the fact that the use of real estate company is not disputed. This decision was deemed reasonable at first appellate court, and after the court of appeal and the Supreme Arbitration Court of Russia. The above position is suited not only to agreements in which there are no conditions that would enable the concrete to determine what areas are the subject of the lease, but also to contracts not registered its members in the manner prescribed by law, as under paragraph 2 of Article 651 CC RF lease of the building, premises or facilities, concluded for a period not less than one year must be registered and is concluded since the implementation of such. The obligation of society to pay the building owner unjust enrichment arises under Article 1102 of the Civil Code when the organization took the wrong room and makes payments under the contract. The amount of unjust enrichment in this case under the existing law enforcement practice is calculated based on the average size of the rental payments for similar transactions. Thus, the repayment of a debt for not concluded a lease of premises is carried out not by bringing an action to recover rent, but by the statements of claims for recovery of unjust enrichment in connection with the use of someone else's property.