These are treated as enforceable contracts here, breach of contract suit against estate under California Family Code.
1612. (a) Parties to a premarital agreement may contract withrespect to all of the following: (1) The rights and obligations of each of the parties in any ofthe property of either or both of them whenever and wherever acquiredor located. (2) The right to buy, sell, use, transfer, exchange, abandon,lease, consume, expend, assign, create a security interest in,mortgage, encumber, dispose of, or otherwise manage and controlproperty. (3) The disposition of property upon separation, maritaldissolution, death, or the occurrence or nonoccurrence of any otherevent. (4) The making of a will, trust, or other arrangement to carry outthe provisions of the agreement. (5) The ownership rights in and disposition of the death benefitfrom a life insurance policy. (6) The choice of law governing the construction of the agreement. (7) Any other matter, including their personal rights andobligations, not in violation of public policy or a statute imposinga criminal penalty. (b) The right of a child to support may not be adversely affectedby a premarital agreement. (c) Any provision in a premarital agreement regarding spousalsupport, including, but not limited to, a waiver of it, is notenforceable if the party against whom enforcement of the spousalsupport provision is sought was not represented by independentcounsel at the time the agreement containing the provision wassigned, or if the provision regarding spousal support isunconscionable at the time of enforcement. An otherwise unenforceableprovision in a premarital agreement regarding spousal support maynot become enforceable solely because the party against whomenforcement is sought was represented by independent counsel.1613. A premarital agreement becomes effective upon marriage.1614. After marriage, a premarital agreement may be amended orrevoked only by a written agreement signed by the parties. Theamended agreement or the revocation is enforceable withoutconsideration.1615. (a) A premarital agreement is not enforceable if the partyagainst whom enforcement is sought proves either of the following: (1) That party did not execute the agreement voluntarily. (2) The agreement was unconscionable when it was executed and,before execution of the agreement, all of the following applied tothat party: (A) That party was not provided a fair, reasonable, and fulldisclosure of the property or financial obligations of the otherparty. (B) That party did not voluntarily and expressly waive, inwriting, any right to disclosure of the property or financialobligations of the other party beyond the disclosure provided. (C) That party did not have, or reasonably could not have had, anadequate knowledge of the property or financial obligations of theother party. (b) An issue of unconscionability of a premarital agreement shallbe decided by the court as a matter of law. (c) For the purposes of subdivision (a), it shall be deemed that apremarital agreement was not executed voluntarily unless the courtfinds in writing or on the record all of the following: (1) The party against whom enforcement is sought was representedby independent legal counsel at the time of signing the agreement or,after being advised to seek independent legal counsel, expresslywaived, in a separate writing, representation by independent legalcounsel. (2) The party against whom enforcement is sought had not less thanseven calendar days between the time that party was first presentedwith the agreement and advised to seek independent legal counsel andthe time the agreement was signed. (3) The party against whom enforcement is sought, if unrepresentedby legal counsel, was fully informed of the terms and basic effectof the agreement as well as the rights and obligations he or she wasgiving up by signing the agreement, and was proficient in thelanguage in which the explanation of the party's rights was conductedand in which the agreement was written. The explanation of therights and obligations relinquished shall be memorialized in writingand delivered to the party prior to signing the agreement. Theunrepresented party shall, on or before the signing of the premaritalagreement, execute a document declaring that he or she received theinformation required by this paragraph and indicating who providedthat information. (4) The agreement and the writings executed pursuant to paragraphs(1) and (3) were not executed under duress, fraud, or undueinfluence, and the parties did not lack capacity to enter into theagreement. (5) Any other factors the court deems relevant.1616. If a marriage is determined to be void, an agreement thatwould otherwise have been a premarital agreement is enforceable onlyto the extent necessary to avoid an inequitable result.1617. Any statute of limitations applicable to an action assertinga claim for relief under a premarital agreement is tolled during themarriage of the parties to the agreement. However, equitable defenseslimiting the time for enforcement, including laches and estoppel,are available to either party.