Reg. § 1.1402(c)-1 Trade or business.
In order for an individual to have net earnings from self-employment, he must carry on a trade or business, either as an individual or as a member of a partnership. Except for the exclusions discussed in , inclusive, the term “trade or business”, for the purpose of the tax on self-employment income, shall have the same meaning as when used in section . An individual engaged in one of the excluded activities specified in such sections of the regulations may also be engaged in carrying on activities which constitute a trade or business for purposes of the tax on self-employment income. Whether or not he is also engaged in carrying on a trade or business will be dependent upon all of the facts and circumstances in the particular case. An individual who is a crew leader, as defined in section (see such section and the regulations thereunder in part 31 of this chapter (Employment Tax Regulations)), is considered to be engaged in carrying on a trade or business with respect to services performed by him after 1956 in furnishing individuals to perform agricultural labor for another person or services performed by him after 1956 as a member of the crew.
[T.D. 6978, 33 FR 15937, Oct. 30, 1968]