A prenuptial agreement or prenup is a contract entered into by 2 people in anticipation of marriage and before marriage. A postnuptial agreement is an agreement or contract entered into by people who are already married.
Many courts around the country have ruled that a contract entered into after marriage is not as strong as a contract entered into before marriage. Courts are very skeptical when it comes to postnuptial agreements because there is inherently a coercive factor in the agreement.
The typical scenario that leads up to a postnuptial agreement is when one spouse wants to keep the marriage going while the other spouse doesn’t. The unwilling spouse draws up a postnuptial agreement for the willing spouse to sign and makes it a condition of staying married. The spouse signs it hoping to save the marriage enough though the terms of the agreement is against his/her interest. This is the very definition of being coerced. If a contract being entered into is not absolutely and entirely voluntary, without any form or coercion, then it cannot be valid.