This is a great question especially in light of another recent yet related question on whether or not a license was needed to operate a business. The quick and easy answer to your question is no. If you own the MLM business, then the answer is yes.
MLM stands for Multi-level Marketing and according to Wikipedia, MLM is a business-distribution model that allows a parent company to market its products directly to consumers by means of relationship referrals and direct selling. This means that independent contractors, associates, sales consultants and agents (there are additional alternate titles than what are listed here) work for and represent the parent company. The parent company is the entity which would need a license to operate.