Ind. Code § 27-4-3-1
It is hereby declared unlawful for any two (2) or more insurance companies writing the same class, or classes, of risks and doing business in this state, directly or indirectly, to enter into any arrangement, contract, agreement, understanding, combination or association to require, coerce or induce any insurance producer or representative of any two (2) or more of such insurance companies within the state of Indiana to refrain from representing other such insurance companies, or to afford any advantage to any insurance producer to refrain from representing other such insurance companies or to impose upon the insurance producer any disadvantage by reason of the insurance producer's acting as representative of other such insurance companies.
IC 27-4-3-1