In the guarantee of understanding, if the price of the transaction is in the form of currency and money and the transaction is void due to the owner's refusal, the seller owes the monetary price. And due to the increase in inflation in basic and non-basic goods and proportionally, the significant decrease in the value of the national currency and the purchasing power of the people, the decrease in the value of the said monetary price is the theme.
The method of compensating the depreciation of the monetary value in the judicial procedure is scattered and different opinions have been issued by the courts of justice in such a way that some courts believe in compensating the depreciation of the monetary value based on the general inflation index that is determined by the Central Bank of the Islamic Republic of Iran, and some believe in compensating the depreciation of the monetary value based on the subjective and partial inflation index.
However, in 1400, the Supreme Court of the country in unanimous decision No. 811 chose to compensate for the decrease in value in the form of subject inflation, and it seems that the compensation for the decrease in the subject matter with the same explanation as stated in the unanimous decision is correct, however, the said method is specific to cases in which the invalidity is due to the fact that the sale is due to a third party or in a direction parallel to it.