Anyone who owns the business has the right to sell it, subject to the approval of a majority of the owners, if there are more than one. A "family' business is still owned by somone or by several people--it's not that just being in the family gives you a stake in it. If it is an LLC or corporation, there is some person or persons who own the LLC or corporation; if it's a formal partnership, there are partners; if it's completely informal, there are still people who own the tools, inventory, furniture, any trademarks, etc. A sole owner of a business can do anything he likes with it; if there is more than one owner the people who together own a majority of it (e.g if there are 5 equal owners, 3 of them) can make that decision. So whether your uncle is the sole owner, or one of the owners (and if so, how many otheer owners are there, how much does each one own, etc.) will provide the answer to your question.