Generally, that will not affect the validity or enforceability of the document. The prenup states that any failure to identify an asset does not affect its enforceability and it remains valid. I also include a waiver of financial disclosure that states that each party waives his and her right to complete financial disclosure, just in case something is accidentally not included.
Keep in mind that it is in each party’s interest to include all of his or her assets. All assets owned prior to marriage are separate property. A prenup serves as a list of the assets of each party in the event that there is ever a disagreement about when an asset was acquired or its value at the time of marriage. A record can be particularly important in the event of a disagreement about the value of an asset at the time of marriage if it changes during the marriage.