Marital assets

We have been married 29 years. 10 years ago my wife started a home business. 4 years ago she moved the business to an office space. 2 years ago the business became an LLC with hers as the only name on the business. A significant amount of start up costs were paid out of my salary. Since she moved her business out 4 years ago she has not paid herself a salary though the business has paid all of it’s own bills, salary, rent, new equipment, supplies, etc.

The question is simple, is her business a marital asset or is it not?

… not a lawyer… but seems yes you are…

Q: Am I entitled to part of my spouse’s business?

A: Generally, an asset such as a business that a spouse owns before the marriage is considered separate property and would be owned by the spouse who started the business. But, if the business appreciates or goes up in value during the marriage, the appreciation value may be considered marital property and maybe divided.
Some states require more than just appreciation during the marriage. For instance, non-owner spouses may have to show they actually contributed to the business, through labor, money or some other contribution before any part of the business or its value will be divided.
The presence of a business can really complicate property division. If you're involved in such a divorce, it might be best to consult an attorney.

Sounds like a marital asset to me.