49 C.F.R. §§ 99.735-81
The duties and obligations of a Government employee (or a special Government employee) do not end when government service terminates by retirement, resignation, or for any other reason. In fact the U.S. Code sets forth specific criminal penalties for certain activities by former Government employees. To summarize broadly, section 207 of title 18, U.S. Code, prohibits a former Government employee from acting as agent or attorney in various types of proceedings and matters on behalf of a non-Government party when the employee was involved in the subject matter while working for the Government. The duration and nature of the prohibitions depend in part on the depth of the employee's involvement in the matter while in Government service. Section 208 of the same title relates to activities performed while a Government employee that benefit an employee's prospective private employer. All Government employees and special Government employees should become familiar with the provisions of the two statutory sections cited, which have been made a part of this regulation as appendix E, so that they will be aware of the restrictions which might affect them upon their termination from the Government service.
49 C.F.R. §§99.735-81