§2409

Even if it does not contradict the provisions of civil law, any form of unjustly taking and keeping the property of others is against the seventh commandment: thus, deliberate retention of goods lent or of objects lost; business fraud; paying unjust wages; forcing up prices by taking advantage of the ignorance or hardship of another.

The following are also morally illicit: speculation in which one contrives to manipulate the price of goods artificially in order to gain an advantage to the detriment of others; corruption in which one influences the judgment of those who must make decisions according to law; appropriation and use for private purposes of the common goods of an enterprise; work poorly done; tax evasion; forgery of checks and invoices; excessive expenses and waste. Willfully damaging private or public property is contrary to the moral law and requires reparation.