Among ObamaCare’s few popular features, even among Republicans, is the mandate to cover adult children through age 26 on the insurance plans of their parents. Although sold as a gratuity, somebody must ultimately pay. In a working paper, Gopi Shah Goda and Jay Bhattacharya of Stanford and Monica Farid of Harvard find “evidence that employees who were most affected by the mandate, namely employees at large firms, saw wage reductions of approximately $1,200 per year.”