排除在外的：any trade or business where the principal asset of such trade or business is the reputation or skill of one or more of its employees
Qualified trade or business
A qualified trade or business means any trade or business other than a specified service trade or business and other than the trade or business of being an employee.
Specified service business
A specified service trade or business means any trade or business involving the performance of services in the fields of health,[44] law, engineering, architecture, accounting, actuarial science, performing arts,[45] consulting,[46] athletics, financial services, brokerage services, including investing and investment management, trading, or dealing in securities, partnership interests, or commodities, and any trade or business where the principal asset of such trade or business is the reputation or skill of one or more of its employees. For this purpose a security and a commodity have the meanings provided in the rules for the mark-to-market accounting method for dealers in securities (sections 475(c)(2) and 475(e)(2), respectively).
footnote 46 For purposes of the similar list of services in section 448, Treasury regulations provide that the performance of services in the field of consulting means the provision of advice and counsel. The performance of services in the field of consulting does not include the performance of services other than advice and counsel, such as sales or brokerage services, or economically similar services. For purposes of the preceding sentence, the determination of whether a person’s services are sales or brokerage services, or economically similar services, shall be based on all the facts and circumstances of that person’s business. Such facts and circumstances include, for example, the manner in which the taxpayer is compensated for the services provided (e.g., whether the compensation for the services is contingent upon the consummation of the transaction that the services were intended to effect). See Treas. Reg. sec. 1.448-1T(e)(4)(iv).
