Computation of 13th-month pay and application of non-diminution of benefits rule
Summary
Central Azucarera de Tarlac attempted to change its 30-year practice of computing 13th-month pay by including additional components beyond basic salary, claiming the previous computation was erroneous. The labor union challenged this change as diminution of benefits. The Supreme Court affirmed lower court rulings that the company's longstanding practice had ripened into a binding policy under Article 100 of the Labor Code's Non-Diminution Rule. The Court rejected the company's error claim, finding the guidelines under P.D. 851 were clear and that changing the computation after 30 years, particularly during labor disputes, demonstrated bad faith. The decision reinforces that consistent, deliberate employment practices become binding contractual obligations that employers cannot unilaterally withdraw, protecting workers' established benefits from arbitrary reduction.
Focus of dispute
Computation of 13th-month pay and application of non-diminution of benefits rule
Legal facts
Central Azucarera de Tarlac, a sugar manufacturing corporation, and its labor union disputed the computation of 13th-month pay. For almost 30 years (since 1975), the company computed 13th-month pay using Total Basic Annual Salary divided by 12, including basic monthly salary, first 8 hours overtime pay on Sunday and legal/special holidays, night premium pay, and vacation/sick leaves. In 2006, following operational disruptions including a strike in November 2004, temporary cessation of operations in April-May 2006, and 15-day rotation work schedule until September 2006, the company changed its computation method. For 2006, it computed 13th-month pay as total earnings divided by 12, excluding the additional components previously included. The union objected, claiming the divisor should be 8 (reflecting 8 months worked) and that the company failed to observe its practice of guaranteeing minimum one-month pay.
Judgement and reasoning
{"Court of Appeals (CA)": "Dismissed the petition for certiorari and affirmed the NLRC decision, finding no reversible error in the NLRC ruling that upheld the long-standing company practice.", "Labor Arbiter (LA)": "Dismissed the complaint and declared that petitioner had the right to rectify the error in computation of 13th-month pay, finding merit in the company's claim that the previous computation was erroneous.", "National Labor Relations Commission (NLRC)": "Reversed the Labor Arbiter's decision, ordering the company to adhere to its established practice of granting 13th-month pay based on gross annual basic pay including basic pay, premium pay for work on rest days and special holidays, night shift differential, and paid vacation and sick leaves. Also ordered observance of guaranteed one-month pay minimum.", "Supreme Court (SC)": "Affirmed the CA decision, ruling that the company's 30-year practice of including additional components in 13th-month pay computation had ripened into company policy that cannot be unilaterally withdrawn under Article 100 of the Labor Code (Non-Diminution Rule). The Court rejected the company's claim of error, finding no doubtful or difficult question of law involved, and noted that the change was made in bad faith after 30 years only when disputes arose. The guidelines for computing 13th-month pay under P.D. 851 were clear from inception."}