In a divorce in Minnesota, any money or property acquired during the marriage is presumed to be marital property, meaning both spouses have an interest in it, regardless of who acquired the assets or whose name it is in. That includes business interests of either spouse. But that doesn't necessarily mean the spouse always "gets half of it" in the divorce. A divorce settlement can award a marital asset to just one spouse. If the asset has significant value, the other spouse can be compensated for their marital interest in it, whatever that may be, with other assets or money. Many small businesses have no real "market value" and so the spouse wouldn't need to be compensated in the divorce decree.

Starting the business after the divorce is final (or after the valuation date in the divorce) would typically make the business a nonmarital asset. Or, I suppose, a post-nuptial agreement of some kind could be signed where the spouse agrees not to seek an interest in the other's (otherwise marital) business, but that can get messy and may be impractical if a divorce is imminent. Marital versus nonmarital assets and their division in a divorce can be complicated issues and you should consult with an experienced family law attorney about this. Probably sooner rather than later.

The details will dictate how you can and should proceed. How close are either to becoming reality. Will others be involved in the business? How are you funding the business? An infinite number of variables exist that prohibits an answer in a free online Q and A. You will need an attorney to assist you with forming the business and the divorce proceedings. Some attorneys, like me, have experience with both. Some attorneys are affordable and some are not.