45 C.F.R. § 156.1250
Issuers offering individual market QHPs, including stand-alone dental plans, and their downstream entities, must accept premium and cost-sharing payments for the QHPs from the following third-party entities from plan enrollees (in the case of a downstream entity, to the extent the entity routinely collects premiums or cost sharing):
[81 FR 12352, Mar. 8, 2016]