Section 70 of the Indian Contract Act, 1872, has the heading “Obligation of person enjoying benefit of non-gratuitous act.” It applies “where a person lawfully does anything for another person, or delivers anything to him, not intending to do so gratuitously.”
If the other person enjoys the benefit, the Act says, the latter is bound to make compensation to the former “in respect of, or to restore, the thing so done or delivered.”