The definition of “employer” in section l of chapter 151F of the General Laws, as appearing in section 48 of chapter 58 of the acts of 2006, is hereby amended by adding the following :-provided, however, that any organization operated on a not-for-profit basis that derives the substantial portion of its operating funds from the commonwealth for the delivery of health and human services shall be eligible to offer enrollment in the state medical insurance program, hereafter referred to as the plan to its full time employees.  To be eligible an organization shall: (1) have as it primary business the provision of health and human services; (2) have conducted this business for 3 years; and (3) participate in the state uniform financial reporting system; provided, however, that “substantial portion” shall mean that state funding comprises 50 per cent or more of the entire organization’s total revenue or the revenue of all its constitute members if it is a part of a controlled group.  Full time employees shall be defined as any employee who works either: (a) the number of weekly payroll hours to be eligible for full time health  plan benefits per the existing definition of the employer ; or (b) 35 or more payroll hours per week.  In order to be eligible to participate, the organization shall charge its employees no more than 20 per cent of the cost of a plan, the same cost that state employees currently pay for the plan.