"Federal and state officials and consumer advocates have grown worried that companies with relatively young, healthy employees may opt out of the regular health insurance market to avoid the minimum coverage standards in [the ACA], a move that could drive up costs for workers at other companies.... 'The new health care law created powerful incentives for smaller employers to self-insure,' said Deborah J. Chollet, a senior fellow at Mathematica Policy Research who has been studying the insurance industry for more than 25 years. 'This trend could destabilize small-group insurance markets and erode protections provided by the [ACA]'."