1. An employer who fails to give notice as required by paragraph (a) of subdivision one of section eight hundred sixty-b of this article before ordering a mass layoff, relocation, or employment loss is liable to each employee entitled to notice who lost his or her employment for:

1. (a) Back pay at the average regular rate of compensation received by the employee during the last three years of his or her employment, or the employee's final rate of compensation, whichever is higher.
2. (b) The value of the cost of any benefits to which the employee would have been entitled had his or her employment not been lost, including the cost of any medical expenses incurred by the employee that would have been covered under an employee benefit plan.

4. The amount of an employer's liability under subdivision one of this section, shall be reduced by the following:

1. (a) Any wages, except vacation moneys accrued before the period of the employer's violation, paid by the employer to the employee during the period of the employer's violation.
2. (b) Any voluntary and unconditional payments made by the employer to the employee that were not required to satisfy any legal obligation.
3. (c) Any payments by the employer to a third party or trustee, such as premiums for health benefits or payments to a defined contribution pension plan, on behalf of and attributable to the employee for the period of the violation.
4. (d) Any liability paid by the employer under any applicable federal law governing notification of mass layoffs, plant closings, or relocations.
5. (e) In an administrative proceeding by the commissioner, any liability paid by the employer prior to the commissioner's determination as the result of a private action brought under this article.
6. (f) In a private action brought under this article, any liability paid by the employer in an administrative proceeding by the commissioner prior to the adjudication of such private action.