In Ricardo E. Vergara, Jr. v. Coca-Cola Bottlers Philippines, Inc. (G.R. No. 176985, April 1, 2013), the Supreme Court held: Generally, employees have a vested right over existing benefits voluntarily granted to them by their employer. Thus, any benefit and supplement being enjoyed by the employees cannot be reduced, diminished, discontinued or eliminated by the employer. The principle of non-diminution of benefits is actually founded on the Constitutional mandate to protect