5 C.F.R. § 8301.102
(b) Definition of employment. For purposes of this section, “employment” means any form of non-Federal employment or business relationship or activity involving the provision of personal services by the employee for direct, indirect, or deferred compensation other than reimbursement of actual and necessary expenses. It also includes, irrespective of compensation, the following outside activities.
(c) Submission of requests for approval. An employee seeking to engage in employment for which advance approval is required shall submit a written request for approval to the employee's supervisor a reasonable time before the employee proposes to begin the employment. Upon a significant change in the nature of the outside employment or in the employee's official position, the employee shall submit a revised request for approval. The supervisor will forward written requests for approval to the agency designee, through normal supervisory channels. All requests for prior approval shall include the following information:
(e) Responsibilities of the component agencies.