20 CFR § 702.285 - Report of earnings.
(a) An employer, carrier or the Director (for those cases being paid from the Special Fund) may require an employee to whom it is paying compensation to submit a report on earnings from employment or self-employment. This report may not be required any more frequently than semi-annually. The report shall be made on a form prescribed by the Director and shall include all earnings from employment and self-employment and the periods for which the earnings apply. The employee must return the complete report on earnings even where he or she has no earnings to report.
(b) For these purposes the term “earnings” is defined as all monies received from any employment and includes but is not limited to wages, salaries, tips, sales commissions, fees for services provided, piecework and all revenue received from self-employment even if the business or enterprise operated at a loss of if the profits were reinvested.