This section and sections 621-A and 622 do not apply to family members and salaried employees as defined in section 663, subsection 3, paragraphs J and K. Sections 621-A and 622 do not apply to an employee of a cooperative corporation or association if the employee is a stockholder of the corporation or association, unless the employee requests the association or corporation to pay that employee in accordance with section 621-A. Except as provided in section 621-A, subsections 3, 4 and 5, a corporation, contractor, person or partnership may not by a special contract with an employee or by any other means exempt itself from this section and sections 621-A and 622. [2005, c. 18, §2 (AMD).]