42 CFR §417.153

1. (a)Basic rule. An employing entity that is subject to this subpart and that elects to include one or more qualified HMOs must offer the HMO alternative in accordance with this section.
2. (b)Employees to whom the HMO option must be offered. Each employing entity must offer the option of enrollment in a qualified HMO to each eligible employee and his or her eligible dependents who reside in the HMO's service area.
3. (c)Manner of offering the HMO option.
   1. (1)For employees who are represented by a bargaining representative, the option of enrollment in a qualified HMO—
      1. (i)Must first be presented to the bargaining representative; and
      2. (ii)If the representative accepts the option, must then be offered to each represented employee.
   2. (2)For employees not represented by a bargaining representative, the option must be offered directly to those employees.