My 401K plan from a job I worked at in Michigan years before marrying my husband; is he entitled to it. We live in and got married in SC.

If your divorce case is pending in South Carolina, The court has jurisdiction to equitably divide all marital assets of the parties, regardless of their current location and regardless of the jurisdiction in which they were accumulated.  The fact these assets were accumulated prior to the marriage would most likely result in them being considered NON -MARITAL, and therefore outside of the reach of your spouse.