Definition of substance vs. form concept

substance is the material or essential part of something, as distinguished from form, which is the observance of a legal or technical manner or order. In some tax situations, the courts and the IRS look past the form to determine the substance of a transaction in order to find out what was done in fact rather than what the taxpayer contends occurred. In other situations, the form controls, even though the substance of the transaction could have resulted from a different form.