A business league is an association of persons having some common business interest, the purpose of which is to promote such common interest and not to engage in a regular business of a kind ordinarily carried on for profit.
To be exempt as a business league, an organization's activities must be devoted to improving business conditions of one or more lines of business (as distinguished from performing particular services for individual persons). It must be shown that the conditions of a particular trade or the interests of the community will be advanced. Merely indicating the name of the organization or the object of the local statute under which it is created is not enough to demonstrate the required general purpose.
No part of a business league's net earnings may inure to the benefit of any private shareholder or individual and it may not be organized for profit to engage in an activity ordinarily carried on for profit (even if the business is operated on a cooperative basis or produces only enough income to be self-sustaining).
To be exempt, a section 501(c)(6) organization must receive meaningful membership support.
Trade associations and professional associations are business leagues. Chambers of commerce and boards of trades are of the same class as business leagues, but rather than promoting one or more lines of business, their efforts are directed to promoting the common economic interests of all commercial enterprises in a given trade community. The requirements for exemption of these organizations are substantially the same as for business leagues.