29 C.F.R. § 552.109 : Labor — REGULATIONS RELATING TO LABOR — WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR — REGULATIONS — APPLICATION OF THE FAIR LABOR STANDARDS ACT TO DOMESTIC SERVICE — INTERPRETATIONS — Third party employment

(a) Third party employers of employees engaged in companionship services within the meaning of §552.6 may not avail themselves of the minimum wage and overtime exemption provided by section 13(a)(15) of the Act, even if the employee is jointly employed by the individual or member of the family or household using the services. However, the individual or member of the family or household, even if considered a joint employer, is still entitled to assert the exemption, if the employee meets all of the requirements of §552.6.
(b) Employees who are engaged in providing babysitting services and who are employed by an employer or agency other than the family or household using their services are not employed on a "casual basis" for purposes of the section 13(a)(15) exemption. Such employees are engaged in this occupation as a vocation.
(c) Third party employers of employees engaged in live-in domestic service employment within the meaning of §552.102 may not avail themselves of the overtime exemption provided by section 13(b)(21) of the Act, even if the employee is jointly employed by the individual or member of the family or household using the services. However, the individual or member of the family or household, even if considered a joint employer, is still entitled to assert the exemption.

29 C.F.R. § 552.109

40 FR 7405, 2/20/1975, as amended at 78 FR 60557, 10/1/2013