Individuals, including domestic workers, foreign spouses, spouses from Mainland China (including Hong Kong and Macao), foreign nationals who have obtained permanent residence, foreign professionals, and foreign specialist professionals, may voluntarily contribute and remit payments, provided they fall into one of the following categories:
I. Workers who do not fall under the Labor Standards Act.
II. The appointed workers.
III. The employers who actually renders the work.
IV. The self-employed operators.