The general approach courts take is that parties should be free, within broad limits, to choose the financial terms of their marriage. While the majority of premarital contracts are enforceable, there are certain standards of due process in formation and substantive fairness that can make these agreements unenforceable or have certain terms in them not enforced.
There was not full financial disclosure. One of the biggest no-no’s during a divorce is attempting to hide assets or information. This is also true in a premarital agreement. As a part of the agreement, you are asserting that each person has given the other full disclosure of all their financial information. If either person does not do that the premarital agreement could be invalidated.
The agreement is extremely one-sided. Prenups are not enforceable if they are found to be “unconscionable” or in extreme favor of one spouse over the other. For example, an agreement that forced one spouse to take all of the marital debt while the other takes no debt may be considered unconscionable. This does not mean that a court will necessarily deem a premarital agreement unconscionable if it awards more money to one spouse than the other. The contract must have an extreme result for it to be unreasonable.
One of the parties was coerced into signing the agreement. When a premarital agreement is signed, it must be voluntarily signed by both parties and they both must be in a state that allows them to understand the terms of the agreement. If one of the parties was coerced into signing the agreement or if they lacked the capacity to understand it, the premarital agreement may be invalidated.
A court may also refuse to enforce a provision of a premarital agreement, without rejecting the entire agreement. This can happen if the court finds that the term is unconscionable at the time of signing, or that it would result in substantial hardship for a party because of a material change in circumstances arising after the agreement was signed. Terms about spousal support might also be struck down if a spouse is forced to seek public assistance under the premarital agreement.