Please indicate whether the business is a corporation, family partnership/LLC/LLP or a proprietorship.
If it is a corporation, then she needs to look at the stock certificates. If it is a non-corporate entity, it will be significantly more complicated.
Since you are in a community property state, I assume that community property was used to purchase the business. If so, it is my understanding that each spouse has a claim to an interest in any property acquired after marriage regardless of who's name is on the titles.
Since I am not an attorney, you will need to consider this post as not being authoritative.